How to know "when the last time" SAPscript/Smartforms is printed?

Dear Gurus,

How to know "the last time" SAPscript/Smartforms is printed?

example :

I have a program ZPYG_FORM and layout ZPYG_LAYOUT

I want know when the last time layout ZPYG_LAYOUT is printed through program ZPYG_FORM?

Cheers!