Am I missing something?

Original posting didn't say anything about blanks in-between.
This point was also implicit in my assumption Iine:
Assume numbers are added sequentially in B2 down

If there are possible blanks in-between data entered down in col B, then in
C2:
=AVERAGE(OFFSET(INDIRECT("B"&MATCH(99^99,B:B)),,,-2))
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Max
Singapore
http://savefile.com/projects/236895
xdemechanik
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