# Definition

N evol corresponds to the change in% between the measurement of a period in year N and its equivalent in N-1

# Calculation formula

N evol = N / (N-1)

# Tip

Certain evolutions, like distributions, are calculated in delta (evolution points) and not in percentage of evolution.

In this case, we subtract N and N-1.

# Special case

In evolution modules, like Sales Evolution, the percentage of the current year ** N Evol ** is the result of the YTD N vs YTD N-1, while the

**is calculated in Year N vs Year N-1 (see screenshot below)**

*N Trend*

Similarly, the evolution of a Current Qtr (therefore a QTD) in Sales Evolution, will be calculated vs the same months in the corresponding QTR N-1 (therefore the QTD N-1).