Inflation based on the wholesale price index (WPI) dropped to 5.66% for the week ended April 28 when compared with 5.77% in the previous week due to lower prices of some food products and manufactured items.Prices of sugar, bajra, gram, barley, poultry chicken, wheat, raw rubber, raw cotton, raw jute, sunflower, fibres and lead ingots declined, according to government data released today.Inflation stood at 3.90% in the corresponding week last year.In food articles, prices of moong, masur and milk moved up while in manufactured items prices of titanium dioxide, building bricks, zinc, pan masala, beedi and biscuits moved up.There was no change in fuel, power, light and lubricants.