Hello everyone,

I have got a panel data set consisting of 12 waves. Every individual has got a unique number called "pid". I have merged the waves in a long format sorted by pid and wave, so each individual has 12 rows of the numerous variables that are in the dataset.

My question is how do i calculate the number of unique individuals who are receiving at least one inheritance (variable= windffy) in the data set?
As when I sum windffy, the number of observations includes individuals who have received an inheritance for more than one of the waves.
(sorry if this is not clear)
Thanks in advance!