This downward revision is likely to happen because since April 17 (the last time copper prices were revised) spot copper prices turned extremely weak and only recovered in the latter half of the fortnight ended April 28. In the third week of April, prices opened extremely week at $1,607 per tonne and staged a recovery to end the month at $1,715 per tonne.

The LME average copper price was $1,644 for the week ended April 21 and $1,708 for the week ended April 28. Based on these averages the landed cost of copper for the fortnight works out to Rs 108,000 per tonne of copper cathode, Rs 111,800 per tonne of copper wire bar and Rs 114,000 per tonne of copper continuous cast (cc) rods. Prices are currently at Rs 1,10,000 per tonne of copper cathode, Rs 1,16,000 per tonne of copper wire bar and Rs 1,18,000 per tonne of copper cc rods.

Domestic copper producers - Hindustan Copper, Sterlite and Birla Copper - review prices every fortnight and revise them upwards or downwards depending on the price trend on the LME in the preceding fortnight.

If there isn't going to be substantial change in prices, adjustments are made by offering or withdrawing the discounts. Domestic prices for a given fortnight are arrived at by taking the weighted average landed cost of imports based on LME prices during the preceding fortnight.

Copper producers have revised their prices five times in the current year. The start of the year witnessed buoyancy in prices and copper producers raised prices. Towards February and March, prices started slipping and producers reduced prices sharply in the second half of March in response to the downtrend in prices and also to boost offtake of the metal before the fiscal year end. On April 1, prices were hiked only to be reduced on April 17 as spot copper prices slid from $1,720 per tonne at the start of April to $1,648 on April 14.

All this volatility in prices has taken place despite the fact the copper stocks have fallen on every day, except one, in April. Stocks were at 7,50,000 tonnes at the start of the month and have fallen by 46,000 tonnes to 7,04,000 tonnes at the end of month.