Hi Friends,
What is the On-Schedule Indicator (OSI)?

The OSI (On-Schedule-Indicator) uses an index of 100 to show a campaign that is pacing to meet delivery goals. ... It's well documented that when multiple ad servers are used to deliver a campaign, discrepancies in reporting ad impressions will occur.

OSI, or on schedule indicator, compares the advertiser spend or total spend to the advertiser spend or total spend that should have been spent.

On Schedule Indicator (OSI) is the percent likelihood the campaign will deliver all impressions booked.