To get a list / count of jobs (or any object) that ran for a specific period, you can run Statistics > Period, and enter the date range and time range (From/Until).
The result is limited to 5,000 rows by default. You can increase this to 20,000 rows (max) in UC_SYSTEM_SETTINGS > GENERIC_STATISTICS_LIMIT.
If your result is over 20,000, another option would be to run a query against the Automation Engine database.
Example - SQL to get the list of all jobs that ran between Oct 5th and Oct 7th
You can modify the query below accordingly (base on what you're looking for)
select oh.oh_client, oh_otype, oh_name,ah.ah_timestamp1 ActivationDateTime, ah.ah_timestamp2 StartDateTime, ah.ah_timestamp4 EndDateTime from ah, ohwhere oh_idnr = ah_oh_idnrand oh_otype in ('JOBS') --- JOBS, JSCH, JOBP, EVNT, SCRI etcand (ah_timestamp1 > '2016-10-05' and ah_timestamp1 < '2016-10-07')