What reporting tool should be used to complete this request?

An administrator is asked to create a report to calculate the year-over―year changed in the dollar amount of a company’s opportunities.

What reporting tool should be used to complete this request?
A . A row-level formula to compare amounts grouped by year.
B . A joined report with two report blocks for each year
C . A custom summary formula with PARENTGROUPVAL function
D . A custom summary formula with the PREVGROUPVAL function.

Answer: D

Explanation:

A custom summary formula is a formula that calculates values from summary fields in reports such as sums, averages, counts, etc. Custom summary formulas can use functions such as PREVGROUPVAL which returns the value of a field from the previous row at the same grouping level. By using a custom summary formula with the PREVGROUPVAL function, an administrator can create a report to calculate the year-over-year change in the dollar amount of a company’s opportunities by subtracting the amount from the previous year from the amount from the current year and dividing by the amount from the previous year.

Reference:

https://help.salesforce.com/s/articleView?id=sf.reports_builder_summary_formulas.htm&type=5

https://help.salesforce.com/s/articleView?id=sf.reports_builder_functions.htm&type=5