Appraisal on house drops like crazy??

Chase bank appraised out house last year at 139.900 when we applied for our home equity. This year we applied for an increase in the home equity (they called us) They said our house is only appraised at 87,000 and wanted to know who said it was 139,900. They seemed suprised when we said them last year. Is this possible. We had siding, and 27 new windows put in just before we got the home equity last year.