Numbers won't randomise for me

I'm trying to randomise a list of 35,000 numbers. They're all in one column and in another column I tried to put in the =rand() formula to create a list of random numbers for each of the numbers in my own list. But for some reason, when I create one random number between 0 and 1 and then try to fill the rest of the column, it just copies and pastes that same number into each row instead of creating a new number. I've done it before and its worked so I'm not sure what I'm doing wrong. Any help is appreciated!