Lead/Lag
The default lead/lag is 0 months. You can specify that the index time series either lead (come before) or lag (come after) the variable being correlated with. You can specify the correlations in months only. So, if you are doing seasonal correlations of FMA, a one month lead would correspond to the index time series of JFM. Please do not specify a lead of more than 12 months. The months used are indicated on the plot.