In a table with your values, the code below will get a record, run an append query for each day in that month.
Code:
sub btnRun_click()
dim rst.
dim iVol as integer
dim vDate,vMo,vEndDate,vStartDate
Docmd.setWarnings false
set rst=currentdb.openrecordset("select * from tSettings")
with rst
While not .eof
VMo=.fields("month").value
VStartDate=vMo & "/1/" & txtYR
VVol =.fields("volume")
VEndDate=dateAdd("d",-1,dateAdd("m",1,vStartDate))
VDate= StartDate
While vDate <= vEndDate
SSql = "insert into table ([date],[volume]) values (#" & vDate & "#," & vVol & ")"
Docmd.runSql sSql
vDate= dateAdd("d",1,vDate)
Wend
.movenext
Wend
end with
set rst = nnothing
end sub