Drag and drop a formula down a single column

In B4 is the word "T Equity". I need a macro to isolate "T" and copy it from A6:T217. Then do the same for the next example "MSFT Equity" in B219 and isolate MSFT and copy it from A221:A256. Do the same form WMT Equity in B258 ect... (More examples will be added over time).

In column A, I have the formula =LEFT($B$4,SEARCH(" ",$B$4)-1) that demonstrates exactly how I would like the data to look. Eventually I am going to have hundreds of these examples and need a macro to perform this task easily.

Can anyone help me out with this? Thanks