sql - Insert new column that adds a series from another column -

i have table dates , follower growth each date , want make new column depicts total followers gained.

how can insert new column adds 'new followers' column in summation series?

date    | new followers -----------------------     1/1/15 |    1 1/2/15 |    3 1/3/15 |    5 1/4/15 |    4 1/5/15 |    3 

new table like

date    | new followers | total followers gained ------------------------------------------------ 1/1/15  |   1           |    1 1/2/15  |   3           |    4 1/3/15  |   5           |    9 1/4/15  |   4           |   13 1/5/15  |   3           |   16 

this sql accomplish want select. if necessary persist value in table, use sql in trigger. since calculate amount on fly, i'm not sure why persist it.

declare @temptable table (thedt datetime, newfollowers int)  insert @temptable select '1/1/15',1 union select '1/2/15',3 union select '1/3/15',5 union select '1/4/15',4 union select '1/5/15',3  select t1.thedt,         t1.newfollowers + sum(case when t2.thedt not null t2.newfollowers else 0 end) "total followers" @temptable t1 left outer join @temptable t2 on t1.thedt > t2.thedt group t1.thedt, t1.newfollowers order t1.thedt