With record volume in 2017, Erie County Medical Center Corp. surpassed its projections for both revenue and performance, ending the year with an operating surplus of $3.2 million. The hospital on Wednesday released financial data for last year, showing revenue of $647.4 million, up 5 percent from 2016, when operating revenue reached $616.5 million. The operating surplus — the largest on record since 2010 — came in spite of costs related to a cyber attack in April 2017, which were balanced…