Scheduled flights are flights that operate on a regular basis, following a set schedule. These flights usually operate between two or more airports and have a specific departure and arrival time. Scheduled flights are typically operated by commercial airlines, such as American Airlines, Delta Air Lines, and United Airlines, and are meant to transport passengers and cargo on a regular basis.
Tracked flights, on the other hand, refer to flights that are being tracked by a system or service, such as a flight tracking website or app. These flights can be either scheduled or non-scheduled, and the tracking information typically includes the flight’s current location, speed, altitude, and other details. Flight tracking can be done by using the Aircraft registration number (tail number), flight number, or the callsign.
Based on the data provided in this excelsheet, number of tracked flights are always less than or equal to the number of scheduled flights. I think it means that the scheduled flights are not always tracked by the flight system.