The Iarussi Legal Aide office assisted $145$ people in June, $2020,$ with a staff labor cost of $$3,210.$ In June, $2021$ the office provided assistance to $181$ people with a labor cost of $$3,720.$ What was their productivity growth over this one$-$year period? Do not round intermediate calculations. Round your answer to two decimal placea. Use a minus sign to enter a negative value, if any.

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