Sorry but
Month-to-date (MTD) is a period starting at the beginning of the current month and ending at the current date
and you don't have the date in the date key field, you only have the month (all the date in the month)
Or I'm missing something?
Anyway, with a date field, d for example (DD/MM/YYYY is the format of the date field)
sum({<d={">=$(=date(monthstart(today()), 'DD/MM/YYYY'))<=$(=date(today(), 'DD/MM/YYYY'))"}>} v)
for YTD replace monthstart with yearstart
