A DECLINE in production of crude petroleum and a slowed down in the growth of petroleum refinery hit the combined output growth of six key infrastructure industries to 4.5% in October compared to a 9.9% growth in the corresponding month last year. Production of crude petroleum registered a negative growth of 0.1% against a growth of 9.3% last year. Petroleum refinery grew by a meagre 2.8% against a growth of 18.1% last October. Growth in electricity generation this October dipped to 4.2% from 9.7% in the same month last year. Coal production saw a growth of 9.2%. Finished steel production rose by 4.8% against 10.6% in October 2006. For the April-October period of the current fiscal year, the growth of the core infrastructure industries declined to 6.2% from 8.9% in the corresponding period of the last fiscal, according to official data released on Thursday. The index of six core infrastructure industries, , which has 26.7% weightage in the Index of Industrial Production (IIP), stood at 237.9 in October versus 227.6 in the same month a year ago, the Commerce & Industry ministry release said