Hours spent each month

Hi folks, I’d like to add a grouped column that will sumif all the hours spent that month.

Seems it should be simple, but my filters, sumifs and such, all the formulas I’ve tried, won’t work.

This filter formula should do what you looking for:
[Table 1].filter([DATE].month()=ThisRow.[DATE].month).[HOURS].sum()


Thanks for that; and saving my sanity. I have an exact duplicate of this table with my actual data and the same formula just doesn’t work there. Now it does, for some reason.