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_28628 ( "Region" text, "Population" real, "% of countrys population" text, "Change in population since 1993" real, "Change in % of countrys population since 1993" text )

### 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_28628 WHERE "% of countrys population" = '4.2'