Find the Running Daily Sum of number of employees hired ever: +------------+-----------+------------+ | hire_date | Employees | TotalHired | +------------+-----------+------------+ | 2000-01-02 | 2 | 2 | | 2000-01-03 | 1 | 3 | | 2000-01-04 | 1 | 4 | | 2000-01-06 | 1 | 5 | | 2000-01-08 | 1 | 6 | | 2000-01-11 | 1 | 7 | | 2000-01-12 | 1 | 8 | | 2000-01-13 | 1 | 9 | | 2000-01-22 | 1 | 10 | | 2000-01-2