accra july 24 reuters  ghanas central bank has raised its main interest rate ghcbireci by 50 basis points to 300 it said on monday after inflation rose for two consecutive months the cocoa gold and oilproducing west african nation is grappling with its worst economic crisis in a generation ghanas consumer inflation edged up in june and may after slowing for four months in a row from a more than twodecade high of 541 year on year in december