CREATE TABLE table_29510 ("Period" CLOB, "Live births per year" CLOB, "Deaths per year" CLOB, "Natural change per year" CLOB, "CBR*" CLOB, "CDR*" CLOB, "NC*" CLOB, "TFR*" CLOB, "IMR*" FLOAT, "Life expectancy total" CLOB, "Life expectancy males" CLOB, "Life expectancy females" CLOB)

What period was the life expectancy at 62.4?
SELECT "Period" FROM table_29510 WHERE "Life expectancy total" = '62.4'
SELECT "Period" FROM "table_29510" WHERE "Life expectancy total" = '62.4'