California is home to an estimated 59.5 million potential customers for pickleball equipment. Last year, 4.0 million customers bought at least one item of pickleball equipment from P. Piper brand. Across the industry, including all brands, 17.0 million customers made at least one purchase in the pickleball equipment category, with overall sales totaling $909.9 million for the year. What was MARKET PENETRATION for pickleball equipment in California last year? (Report your answer as a percent. Report 25.5%, for example, as "25.5". Rounding: tenth of a percent.)