Bobe Air uses two measures of activity, flights and passengers, in its cost estimates. The cost formula for plane operating costs is $50,000 fixed costs per month plus $5,000 per flight plus $20 per passenger. The company expected its activity in April to be 150 flights and 600 passengers, but the actual activity was 140 flights and 610 passengers. The actual cost for plane operating costs in April was $752,000. What percent of the variance between the static budget and actual results was due to spending efficiencies (i.e. not activity)? Enter as a whole number, ex: 25