Get each month total and average based on date

hi sturlaw,

Thank you for your quick response

here is the result that i get from the formula,if you see, i'm not sure what the values are displaying here for the month of april , may and june.

here is my need, i have the below sample data

from here for each id, i need max date and the orresponding days.

from here i need to total and average per month

in my data, for january, i dont see any data, so the value is zero

and for month february, i see 2 results, 2.9+0.1 =3, the total is 3 and the average for the month is 3/2(based on no of id's) = 1.5 and the same  for march sum = 64.2 and the count of id's is 15, so the average value is total/count of the id's

which 64.2/15=4.28

so the final report what i need is

Can you help me please,

Thank you