In a marine sanctuary, green sea turtles (Chelonia mydas) are monitored during the nesting season. The nesting population is divided into mainland nesters and atoll nesters.
The table below shows data on the nesting female turtle population in this sanctuary in March 2012 and March 2022.
| Date | Total number of nesting female turtles / thousands | Percentage of Atoll nesters (%) | Percentage of Mainland nesters (%) |
|---|---|---|---|
| March 2012 | 12.80 | 45 | 55 |
| March 2022 | 15.60 | 48 | 52 |
Use the table to calculate the increase in the number of atoll nesting female turtles in the sanctuary between March 2012 and March 2022.
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