Medium Advanced Excel Interview Questions

Number formatting only changes how a value looks; Excel still adds the full decimals stored in each cell. So the sum of hidden paise differs from the sum of the rounded figures shown. If the report must add up exactly as displayed, round the values with =ROUND(value,0) in the source formulas rather than using the Precision as displayed option, which permanently changes stored data for the whole workbook.

Protect Sheet stops edits to locked cells; you first unlock input cells through Format Cells > Protection so users can type only there. Protect Workbook locks the structure, so sheets cannot be added, deleted or renamed. Encrypt with Password (File > Info) is the only option that blocks opening the file. Sheet and workbook protection are about preventing accidents, not real security, because they are easy to bypass.

First highlight duplicates with Conditional Formatting > Highlight Cells Rules > Duplicate Values to review them. Then work on a copy of the sheet and use Data > Remove Duplicates, selecting the key columns such as Mobile and Email. In Microsoft 365 a non-destructive option is =UNIQUE(A2:C500) on a new sheet. Always record how many rows were removed so the change can be explained later.

Situation: a monthly MIS was due to leadership in an hour. Task: I was doing a final review. Action: I noticed the region totals did not match the grand total, traced it to a SUMIFS range that stopped at row 500 while data had grown to 620 rows, converted the source to a Table and re-checked totals against the raw export. Result: the report went out on time with correct numbers, and I added a reconciliation check cell to the template.

Situation: a regional sales summary I sent showed one zone 18% higher than actual. Task: correct it before decisions were taken. Action: I traced it to a SUMIFS range that stopped one row short, sent a corrected file within the hour with a short note explaining the cause, and added a check cell comparing the summary total to the raw data total. Result: the manager appreciated the quick ownership and the check now catches such gaps automatically.

Usually one value is text and the other is a number, so =A2=B2 returns FALSE even though both show 100. Other causes are hidden spaces, or floating-point results like 99.9999999 that display as 100 because of formatting. Check with ISTEXT, LEN and by widening decimals. Fix with VALUE or TRIM on the text side, or compare with ROUND(A2,2)=ROUND(B2,2) for calculated numbers.

Situation: my manager was unsure why the new incentive sheet showed lower payouts. Task: explain the logic without formulas. Action: I added a one-page summary with the slab table, walked through two real employees step by step, and used colour to show which inputs drove the result. Result: the manager understood it in one meeting, approved the sheet and asked me to add the same summary to future models.

Check that the last argument is FALSE, then compare the two values directly with =A2=Sheet2!A5. Common causes are trailing or non-breaking spaces, one side being a number and the other text (like employee codes), and the lookup value sitting outside the first column of the range. Use LEN to spot hidden characters, and fix with TRIM, CLEAN, VALUE or by making both columns the same data type.

Situation: a monthly incentive sheet used VLOOKUP with the last argument left blank, so it ran an approximate match. Task: I was asked to verify payouts before release. Action: I spotted employees getting a neighbour's target, changed every lookup to exact match with XLOOKUP, and added a count of missing IDs. Result: twelve wrong payouts were corrected before payment, and exact match became our team's standard rule.

INDIRECT converts text into a reference, so =SUM(INDIRECT(B1&"!C2:C100")) sums the sheet whose name is typed in B1. It is useful for summary sheets that switch between months and for dependent dropdowns. The risks are that it is volatile, it breaks silently when sheets are renamed, it does not work with closed external workbooks, and formula auditing tools cannot trace it. Use it sparingly.

In Microsoft 365, a formula can return many values that spill into nearby cells, as with UNIQUE, FILTER, SORT and SEQUENCE. Other formulas can refer to the whole result with the spill operator, for example =COUNTA(E2#). #SPILL! appears when the spill area is blocked by data, the formula sits inside a Table, the area overlaps merged cells, or the result would run past the sheet edge. Clear the blocking cells to fix it.

Create a common key, for example date plus amount plus cheque or UTR number. On each sheet add =IF(COUNTIFS(Other[Key],[@Key])=0,"Missing","Matched") and filter the Missing rows. Duplicated amounts need COUNTIFS on both sides so counts are compared, not just presence. For repeated monthly work, load both into Power Query and use Left Anti and Right Anti merges, which list unmatched rows directly.

Do not look up by name alone, because a duplicate name returns the first match and silently assigns sales to the wrong person. First flag duplicates in the master with COUNTIF(names,name)>1. Then build a composite key, such as name plus branch or name plus email, in both tables and look up on that. Rows still ambiguous should go back to the data owner for an ID rather than be guessed.

Situation: finance and sales reported different revenue for the same quarter. Task: find the gap before the review meeting. Action: I pulled both datasets, built a key on invoice number, and used lookups to list invoices present in only one file. Most of the gap came from credit notes that sales did not deduct and invoices booked on the last day. Result: both teams agreed a single definition and I added a reconciliation tab to the monthly pack.

First confirm everyone who opens the file has Microsoft 365 or Excel 2021, because older versions show #NAME? for XLOOKUP. Save a backup, list the VLOOKUPs using Find with Look in: Formulas, and replace them sheet by sheet, keeping an exact-match default. Compare key totals before and after, document the change in a notes sheet, and keep a version that still uses INDEX/MATCH if external clients need it.

Right-click a date in Rows and choose Group to group by days, months, quarters or years; for numbers, group by a range such as 0 to 100000 in steps of 10000 to create sales bands. Grouping fails with the message Cannot group that selection when the column contains blanks, text values or dates stored as text. Clean the source column, refresh, and grouping works.

A calculated field creates a new value field from other fields, such as Margin = Profit / Sales, and it works on the summed totals. A calculated item creates a new member inside a field, such as North + East as a combined region. Calculated items cannot be used with the Data Model, can double-count in totals and slow pivots, so many analysts prefer grouping or a source column instead.

When a pivot is created, Excel stores a snapshot of the source data called the pivot cache, and the pivot reads from it, not directly from the sheet. That is why changes need a refresh. Pivots built from the same Table share one cache, which keeps file size down and lets slicers connect across them. Creating pivots from different copies of the data creates separate caches and makes the file heavier.

A normal pivot only offers Count, which counts every row. When inserting the pivot, tick Add this data to the Data Model. Then in Value Field Settings choose Distinct Count, which counts unique customer IDs per region or month. Alternatively, create a DAX measure =DISTINCTCOUNT(Sales[CustomerID]) in Power Pivot, which can be reused across pivots.

Pivot date grouping uses calendar quarters, so add a helper column in the source data. For example, fiscal quarter ="Q"&ROUNDUP((MOD(MONTH(A2)-4,12)+1)/3,0) and a fiscal year column. Use them as row fields instead of grouped dates. In Power Query or a Data Model, put these columns in a proper Date table so every report uses the same April to March logic.

A pivot chart always follows its pivot, so it cannot be frozen while the pivot is filtered. Options: copy the chart and paste it as a picture into the slide; or copy the pivot values to a normal range and build a regular chart from them; or create a second pivot from the same cache, set its filters once and protect the sheet. For a live report, keep the interactive version on a separate sheet.

Put Region and then Product in Rows, and add Sales to Values twice. For the second copy, open Value Field Settings > Show Values As > % of Parent Row Total. Each product then shows its share of its own region, and each region totals 100 percent. Using % of Grand Total instead would show share of the whole company, which answers a different question.

Open PivotTable Options > Layout & Format, untick Autofit column widths on update and tick Preserve cell formatting on update. Set number formats through Value Field Settings > Number Format rather than formatting cells directly, because field-level formats survive refresh and layout changes. For a consistent look across reports, create a custom PivotTable Style and apply it to every pivot.

Put all files in one folder and use Data > Get Data > From File > From Folder > Combine & Transform. Power Query appends them using the first file as a sample, adds the source file name as a column and applies the same cleaning steps. Load the result as a Table or to the Data Model and build the pivot on it. Next year, adding a file to the folder and clicking Refresh All updates everything.

Situation: at 5 PM, my manager needed customer-wise outstanding for a client call at 9 AM. Task: deliver an accurate summary quickly. Action: I confirmed the exact question and cut-off date, pulled the ledger, built a pivot by customer and ageing bucket, cross-checked the total with the trial balance and flagged three unusual balances. Result: the report was ready by 7 PM, and my notes helped the manager answer follow-up questions in the call.

Situation: I had to present quarterly branch performance to regional directors. Task: make twenty pages of tables understandable in ten minutes. Action: I built one dashboard sheet with four KPIs against target, a trend chart and a ranked bar chart of branches, and kept detail tables as backup. I opened with the key message and the two branches needing action. Result: the meeting ended with clear decisions, and the format became the standard quarterly review pack.

A combo chart shows two series with different chart types, for example monthly sales as columns and margin percentage as a line. The percentage would be invisible on the same scale as crores of sales, so it is plotted on a secondary vertical axis on the right. Label both axes clearly, because readers can misread which series belongs to which scale.

Select the Month, Sales and Margin % columns and go to Insert > Recommended Charts > All Charts > Combo. Set Sales to Clustered Column and Margin % to Line with Markers, ticking Secondary Axis for Margin %. Add axis titles, format the secondary axis as 0%, add data labels only to the line if needed, and remove gridline clutter. Give it a title that states the insight, such as Margin fell while sales grew.

A waterfall chart shows how a starting value moves to an ending value through a series of positive and negative steps. It is common in finance for profit bridges, such as last year's profit, plus volume growth, minus price discount, minus higher costs, giving this year's profit. Excel 2016 and later include it under Insert > Waterfall; set the first and last bars as totals so they start from zero.

Start from the questions the audience asks. Put three to five headline KPIs at the top, trends and breakdowns below, and filters such as slicers in one consistent place. Use one colour palette with a highlight colour for what matters, avoid 3D and decorative effects, label units clearly like Rs lakh, and fit the view on one screen. Keep raw data and calculations on separate hidden sheets.

Clarify the audience, KPIs and refresh frequency first. Load and clean the data through Power Query into a Table or the Data Model. Build pivots for each view on a calculation sheet, create pivot charts, and connect slicers for region, product and month to all pivots. Add KPI cards using GETPIVOTDATA, format consistently, protect the layout and test that Refresh All updates everything when new data is added.

Form controls are added from the Developer tab > Insert. Each control writes a value into a linked cell: a combo box writes the position of the selected item, a check box writes TRUE or FALSE, and a scroll bar writes a number within a set range. Formulas such as INDEX, CHOOSE or FILTER read that cell to change the chart data, so the dashboard reacts without any macros.

Create a clustered column chart with Target and Actual series. Format the Target series with no fill and a thick outline or a light colour, set Series Overlap to 100 percent so both bars sit on top of each other, and make the Actual bar narrower by putting it on the secondary axis with a larger gap width. Match both axis scales. Readers immediately see whether Actual falls short of or crosses the target.

A histogram groups numeric values into bins and shows how often each bin occurs, for example how many orders fall between 0 to 1,000 rupees or 1,000 to 5,000 rupees. A Pareto chart sorts categories by frequency and adds a cumulative percentage line, showing the vital few, such as the 20 percent of complaint types causing 80 percent of complaints. Both are available under Insert > Statistic Charts.

The most common cause is a column or bar chart whose vertical axis does not start at zero, which exaggerates small differences. Other issues are inconsistent scales between side-by-side charts, a secondary axis that is not labelled, 3D effects distorting sizes, missing months making a trend look smooth, or totals mixed with categories. Fix the axis, label units and state the time period in the title.

Options depend on the message. Sort bars and show the top items with the rest grouped as Others; split into two charts, one for the giants and one for the rest; add data labels so small values are still readable; or use a logarithmic axis for technical audiences, clearly labelled. Avoid cutting the axis on bar charts, because bar length then stops representing value and misleads readers.

Decide what they need: a view or a working file. For a view, export the dashboard sheet to PDF or share a view-only link from SharePoint or OneDrive. For a file, save a copy, break external links, paste pivots or formulas as values if needed, remove hidden sheets and personal data with Inspect Document, and protect the sheet. Automate the steps with a macro or Office Script so every week is identical.

Since Excel files cannot restrict data inside a workbook securely, create separate files. Add a Region parameter cell that drives Power Query filters or pivot filters, then loop through regions with a short VBA macro that sets the region, refreshes, removes other data and saves a copy or PDF per region. For regular use at scale, Power BI with row-level security is the better solution.

Situation: I built a sales dashboard with eight charts for the regional team. Task: get it adopted. Action: in the review, managers said they only checked target achievement and the bottom five branches each morning, so I moved those to the top, removed four rarely used charts and added a branch slicer. Result: usage went up, the meeting started using it daily, and I learned to ask what decisions a dashboard supports before building it.

Place files with the same structure in one folder. Go to Data > Get Data > From File > From Folder, select the folder and click Combine & Transform. Choose the sheet or table from the sample file; Power Query creates a helper function and appends all files, adding a Source.Name column with the file name. Apply cleaning steps once, Close & Load, and later just drop new files in and Refresh.

Left Outer keeps all rows from the first table and matches from the second, the most common choice. Right Outer does the reverse. Full Outer keeps all rows from both. Inner keeps only matching rows. Left Anti keeps rows in the first table with no match, and Right Anti keeps rows in the second with no match. Anti joins are excellent for finding missing invoices or customers during reconciliation.

Load the data into Power Query, select the identifying columns such as Branch and Product, then right-click and choose Unpivot Other Columns. The month headers become an Attribute column and the numbers become a Value column; rename them to Month and Sales. Using Unpivot Other Columns rather than Unpivot Columns means new months added later are included automatically on refresh.

A worksheet holds at most 1,048,576 rows, so the result will not fit. Choose Close & Load To and select Only Create Connection with Add this data to the Data Model. The model compresses data and can handle many millions of rows, and you analyse it with a pivot table or DAX measures. If users only need summaries, group the data inside Power Query before loading.

Select the column, choose Split Column > By Delimiter, enter space-hyphen-space as a custom delimiter and split at each occurrence. This gives ID, Name and City columns. Then use Transform > Format > Trim and Clean to remove extra spaces and hidden characters, Capitalize Each Word for names, and set correct data types. Split by Number of Characters handles fixed-width codes like state and branch prefixes.

Data types decide how values are sorted, summed and loaded, so a number stored as text will not total and a date stored as text will not group by month. Power Query adds an automatic Changed Type step that hard-codes every column name, so a renamed or removed column later causes refresh errors. Many analysts delete it and set types once, deliberately, after the structure is final.

The source file's header changed, for example Amount became Amount (Rs), and a step that refers to the old name, often Changed Type or Renamed Columns, breaks. Open the query, click through the steps to find the first error, and update the name or rename the column back early in the query. To prevent repeats, agree a fixed template with the data owner and avoid steps that list every column unnecessarily.

The system locale is probably English (United States), which reads dates as mm/dd/yyyy, so 13/04/2026 becomes an error and 05/04/2026 becomes 4 May. In Power Query, right-click the column > Change Type > Using Locale, choose Date and English (India). This tells Power Query how to read the text regardless of the computer's settings, so the file refreshes correctly on any machine.

Situation: our team spent a day each month cleaning vendor files by hand. Task: I believed Power Query could fix it but the team feared a new tool. Action: I rebuilt one month's cleanup as a query, then ran it side by side with the manual process and showed identical results in five minutes. I documented each step and trained two colleagues. Result: the team adopted it, saving about eight hours a month.

A parameter is a named value, created in Manage Parameters, that queries can reference instead of a hard-coded value. A common use is a FolderPath parameter so the same workbook works when moved to another computer or shared drive. Parameters can also hold a cut-off date or a region filter. Changing one value updates every query that uses it, which makes files easier to hand over.

Duplicate copies all steps of a query into an independent new query, so changes to the original do not affect it. Reference creates a new query whose source is the output of the original, so it inherits any future changes. Use Reference to build several outputs from one cleaned staging query, such as a monthly summary and a customer list, so the cleaning logic lives in one place.

Use Get Data > From PDF or import the converted file, then promote the first row to headers. Filter out rows where the first column equals the header text, such as Name, and rows containing footer text like Page or Printed on, using Text Filters > Does Not Contain. Remove blank rows, Fill Down any group labels, and set types. The steps then run automatically on next month's PDF.

Check row counts against the source, then look for duplicate keys, blanks in mandatory fields, inconsistent text such as Delhi and New Delhi, extra spaces and mixed case, dates stored as text or in the wrong locale, negative or extreme numbers that look like typos, and codes losing leading zeros. Power Query's Column Quality and Column Profile views show errors, empties and distinct counts for each column quickly.

Situation: every Monday I merged five regional order files and cleaned them by hand, which took about three hours. Task: reduce the effort and errors. Action: I built a Power Query folder import, standardised columns, fixed date locale issues and loaded the result to a pivot dashboard, then wrote a one-page guide for the team. Result: the job took ten minutes, copy-paste errors disappeared and two other teams adopted the same setup.

A calculated column is computed row by row when data is refreshed and stored in the table, like Sales[Margin] = Sales[Amount] - Sales[Cost]. It uses memory and can be used in rows, columns and slicers. A measure is computed on the fly for each cell of a pivot based on its filters, like Total Margin = SUM(Sales[Margin]). Use measures for aggregations and calculated columns only for attributes you slice by.

RELATED is used on the many side to fetch a single value from the one side, such as getting a product's category in each sales row. RELATEDTABLE is used on the one side to return all matching rows from the many side, so in Products you could write Order Count = COUNTROWS(RELATEDTABLE(Sales)). Both need an existing relationship and a row context.

Create a hierarchy in the Date table in Power Pivot diagram view, such as Year > Quarter > Month, so users drag one field and drill down. Set Month Name to sort by Month Number so months do not appear alphabetically. Hide key columns and raw fields that should not be used directly, and give measures clear business names. This keeps the field list small and the pivots consistent.

Both use the same VertiPaq engine and the DAX language, and both use Power Query for data preparation. A Power Pivot model can be imported into Power BI Desktop through File > Import, carrying queries, relationships and measures. This makes Advanced Excel with Power Pivot a natural stepping stone, since most of the model and DAX skills transfer directly to Power BI.

Common causes are hard-coded file paths or user names, missing library references shown as MISSING in Tools > References, macros blocked by Trust Center settings or because the file came from the internet, and 32-bit versus 64-bit Office, which needs PtrSafe in API declarations. Different regional settings for dates and decimals, or a renamed sheet, also break code. Use ThisWorkbook.Path and late binding to make macros portable.

A UserForm is a custom dialog box with text boxes, dropdowns, option buttons and command buttons, created in the VBA editor through Insert > UserForm. It is useful for controlled data entry, such as an employee or expense entry form that validates inputs before writing a row to a Table, or for letting users choose options before a report macro runs. It reduces errors from typing directly into sheets.

Situation: I wrote a macro that split a master file into branch-wise reports for 30 branches. Task: others had to run it while I was on leave. Action: I added Option Explicit, comments, a settings sheet for paths and branch lists, error handling with clear messages and a short user guide. Result: colleagues ran it for months without my help, and adding new branches needed only a row in the settings sheet.

Macro actions clear Excel's undo history, so prevention matters. Add a confirmation prompt before destructive steps, test on a copy of the file, and have the macro save a backup copy with a timestamp before it changes data. Restrict deletion to clearly identified ranges such as a named Table, not ActiveSheet. For files on OneDrive or SharePoint, version history can usually restore the earlier copy.

Situation: a report macro I wrote stopped working for the accounts team. Task: fix it quickly and stop it happening again. Action: I found that a sheet had been renamed and the macro used a fixed sheet name and file path. I fixed it with ThisWorkbook.Path and code names, added an error handler with a clear message, and wrote a short usage note. Result: it ran reliably for the rest of the year and I now test macros on another user's machine before handover.