This formula calculates the difference between a given date (H11 in the example) and today,
and formats it as Y years, M months
, or just M months
if Y=0
CONCAT(
IF(DATEDIF(H11;today();"Y") > 0;
DATEDIF(H11;today();"Y") & " years, ";
""
);DATEDIF(H11;today();"YM") & " months")