The number of jobs in New York’s film production sector grew significantly from 32,500 in 2004 to 46,100 last year as the state sweetened its production tax incentive program, according to a study commissioned by the MPAA.The findings, from HR&A Advisors Inc., come as tax credits have come under new scrutiny in some states, either from a series of scandals or doubts over how effective they have been at creating last jobs. The New York Times has been running a series, “The United States of Subsidies,” examining business incentives overall, and it was expected to focus on the film business today. The HR&A study, however, painted a rosy picture of the impact of the production incentives, estimating that the state’s production tax credit, which took effect on Nov. 1, 2004, supported 28,900 jobs last year, including 12,600 directly associated with productions and 16,300 through “multiplier effects.” The latter is an estimate of the jobs created in other industries, like retail, hospitality and professional services, boosted by the growth in production. The study also showed that, even as private employment declined by 1.6% statewide from 2008 and 2011, jobs in film production grew by nearly 25%. The credit, the study said, generated $6.9 billion in economic spending and $4.2 billion in personal income in 2011. The state collected an estimated $366 million in taxes from such activity, while New York City collected $382 million in taxes due to the credit last year, the study concluded.