Table: governor_successors_2
Columns: state_class
vacator
reason_for_change
successor
date_of_successors_formal_installation

Question: List the number of vacators when successors were formally installed on June 22, 1868.
SQL: SELECT COUNT("vacator") FROM governor_successors_2 WHERE "date_of_successors_formal_installation" = 'June 22, 1868'

Question: List all state classes when successors were formally installed on June 22, 1868.
SQL: SELECT "state_class" FROM governor_successors_2 WHERE "date_of_successors_formal_installation" = 'June 22, 1868'