According to what rule have I assigned each President the number listed?

• Everyone before Coolidge - N/A

• Coolidge - 0

• Hoover - 0

• FDR - 3

• Eisenhower - 2

• Truman - 2

• Kennedy - 1

• Johnson - 2

• Nixon - 2

• Ford - 0

• Carter - 1

• Reagan - 2

• GHW Bush - 1

• Clinton - 2

• GW Bush - 2