Home sales continued their modest upward swing in May, according to a closely watched industry report that rose for the fourth straight month for the first time in nearly 5 years. The Pending Home Sales Index, reported Wednesday by the National Association of Realtors (NAR), rose 0.1% during the month. The index was up 6.7% compared with May 2008. It was the first four-month run up in the pending sales measure since October 2004. Industry prognosticators had forecast no growth at all in the index for the month, according to Briefing.com, expecting it to settle back after ramping up 6.7% in April. NAR’s Housing Affordability Index remains near historic highs, although it declined in May to 171.6 from 178.8 a month earlier. That was the high point for the index, which dates back to 1970.