Hi Swapnil,
From the screen shot Its evident,
1. Difference is 1500 correct TCR as on 03.03.2015 is 1600 and on 05.03.2015 TCR is 3100 (3100-1600 = 1500).
2. Its counter overflow because on 05.03.2015 TCR is 3100 and then reading entered on 04.04.2015 is 2100. Which is less than 3100 so system consider that counter is completed with one full round.
Please check the individual measuring document to find out either counter reading is entered or difference is entered.
Regards
Varun.M