Associated Builders and Contractors Contractors confidence increased in April despite ongoing challenges.  The Associated Builders and Contractors Backlog Indicator  increased to 8.8 months in April , according to respondents in a survey conducted by the association. Backlog is up 0.2 months on a monthly basis and has risen 0.1 months year-over-year. “While backlog surged to a 10-month high in April, the industry’s recent momentum is highly concentrated among a subset of contractors,” said ABC Chief Economist Anirban Basu in a statement. Basu points to “booming data center construction” as the main catalyst for the increase, noting that “42% of contractors with more than $100 million in annual revenues are under contract to work on data center projects.” Additionally, he says, contractors with data center projects report an average backlog of 12.2 months, while those without projects in the sector show a markedly shorter backlog of 8.3 months.…