sum (add) every consecutive N cells in a column

Hello,

I have several thousands of numbers in a column. I would like to add every 100 cells and bring the result into column B. Can someone help me with this?

For example if I have numbers in 1000 cells from A1 to A1000. Now, I would like to add each consecutive 100 numbers (like A1:A100, A101:A200, A201:A300 and so on) and put the results in column B.

Please help me with this. Thanks