Type of Firm 1966 1970 1974 Petroleum 11.2 9.3 12.7 Drugs 10.8 9.4 12.2 Chemicals 8.0 5.0 8.2 Motor Vehicles 6.2 2.4 2.7 Electrical 4.8 3.3 3.9 Food 2.7 2.5 2.8

Which industry had the least percentage decline in profits as a percentage of sales between 1966 and 1970?

What was the percentage decline (to the nearest tenth)?