At the beginning of the year, Donpo Company initiated a quality improvement program. To help assess the impact of the quality improvement program, the following data were collected for the current and preceding years:
|Annual data||Last Year||This Year|
|Lost sales from customer complaints||\$180,000||\$160,000|
|Product warranty claims||\$36,000||\$24,000|
For this year, what is the external failure cost as a percent of sales?