Edited sentence: Other groups of hospital employees have gone through layoffs and have not had wage increases, but the nurses think they deserve one.The MNA has threatened to strike again on July 6, 2010, and this time the union will have a open-ended strike.The hospitals cannot afford to contribute as much to their pensions as they have in years past, it is unsustainable.The hospitals cannot afford to give them a wage increase this year.The nurses want guaranteed nurse to patient staffing ratios, although these have not been proven to improve patient safety, and the Minnesota hospitals are already amongst the safest in the nation.The union held a historic strike on June 10, 2010, where more than 12,000 nurses walked out on their patients, to protest against the following issues: