Hello again,

Let us have a look at current suggestions.

I tested them on 1000 rows with random integers between 1 and 999.

Calculation time in milliseconds (FastExcel) was:
Bernd 0.96
Ken 1.25
JMB 12.32
Lori 114.84
Harlan 534.70

The (optimal?) non array solution (B1: =A1, B2: A2+B1, copy down) took
0.51

Regards,
Bernd