This formula counts blank cell since the last entry in the colmn.
=IF(L3<"",COUNTBLANK(INDEX($L$2:L2,MATCH(9.999999 99999999E+307,$L$2:L2))
:L3),"")

I find myself needing to manually copy it down to get it to accept the
newest entry.

I have put the formula into a new sheet and make reference to the original
sheet.
=IF(Sheet1!L3<"",COUNTBLANK(INDEX(Sheet1!$L$2:L2, MATCH(9.99999999999999E+307,Sheet1!$L$2:L2))
:Sheet1!L3),"")

Is there a way to make this formula say, a full row reference, that will
automatically count blank cells since the last entry so I don't have to
continually update the formula?

Hope this makes since,
Thank you now, and well into the future for your graciousness,
Luke