Below is the list of tables from the database along with their columns and datatype. Need to generate an accurate SQL query for the question.
Only use the columns present in the respective table. Only use the columns which are required to generate the SQL query. Only use table joins if required and not otherwise.

### Tables ###
TABLE: CREATE TABLE table_2637317_1 (change_in_population_since_1993 VARCHAR, _percentage_of_countrys_population VARCHAR)

### Question ###
What is the change in population since 1993 in the region where the % of country's population was 4.2? 

### Accurate SQL ###

SELECT COUNT(change_in_population_since_1993) FROM table_2637317_1 WHERE _percentage_of_countrys_population = "4.2"