One zero month can kill a revenue report. Here is how to get percent change without errors or lies.
POWER: Why an Integer Base Changes Fractional Results
POWER uses the base type when returning a result. Cast before calculation when fractional results matter and inspect decimal precision and scale.
ACOS: Check the Cosine Domain Before Calculating Angles
ACOS calculates an angle from a supported cosine ratio. Keep invalid and missing inputs visible while displaying valid radians at a chosen scale.
Decimal Precision and Rounding in SQL Server
Decimal precision in SQL Server controls arithmetic results and rounding; use explicit scales, test boundaries, and compare money with decimal.
ASIN: A Sine Ratio Does Not Recover Every Original Angle
ASIN returns an angle from a sine ratio. Preserve the original branch, use explicit units and keep invalid or missing ratios visible.