Brown's, a local bakery, is worried about increased costs particularly energy. Last year's records can provide a fairly good estimate of the parameters for this year. Wende Brown, the owner, does not

believe things have changed much, but she did invest an additional $$3,000$ for modifications to the bakery's ovens to make them more energy efficient. The modifications were supposed to make the

ovens at least $15\%$ more efficient. Brown has asked you to check the energy savings of the new ovens and also to look over other measures of the bakery's productivity to see if the modifications

were beneficial. You have the following data to work with:

Energy productivity increase $=,\%($enter your response as a percentage rounded to two decimal places and include a minus sign if necessary$).$