Weak performances in sectors like cement, coal and finished (carbon) steel lead to a marginal growth of 7.4% in the index of six core infrastructure industries during April 2007, as against 7.3% during April 2006.The cement sector registered a growth of only 5.1% during April 2007, as compared to 12.2% in April 2006. Cement production during the past five months has been sliding. Industry sources attribute it to low settlements in the supply linkage agreements as well as a slow down in the realty sector due to hardening interest rates.Coal production grew 0.5% as against 3.4% in April last year. Production of finished steel increased 8.4% in April 2007 as against 10.1% in the corresponding month of the previous year.Improved production of crude petroleum, refined petroleum products and electricity generation fuelled the marginal growth in the index.During April 2007, crude oil production increased 1.4% against a negative growth of 1.8% in the same month of the previous year.Petroleum refinery products registered a growth of 15.1% as against 13.1% in Apri 2006.The onset of summer pushed up electricity generation during April 2007, which increased 8.7% as against 5.9% in the same month of the previous year.