Can't understand total aircraft stats.

FlightAware ADS-B Flight Tracking
1

I am confused about my total aircraft seen stats.

I am on EST in USA and it seems my daily timer restarts at 8 PM. The last complete period shows 2057 aircraft but when I add up each square for the day (24) from 8 PM to 8PM I get 5293 aircraft.

How does this work exactly?

For today I still have about 4 hrs left at posting and it is showing 1810 total aircraft and I am sure at 8PM it will still only show about 2050 despite way more showing in the squares.

2

It counts unique aircraft; if you just add the hourly totals you are double-counting any aircraft that you saw in more than one hourly bucket.