IBM Corp shares really took fright on further consideration of the analysts’ meeting on mainframes on Wednesday and the shares were down $1.50 at $89.125 in mid-morning trading: IBM said that mainframe revenues for all of 1992 will equal or grow slightly from last year’s $14,000m; revenues in the first half rose more than the whole company’s 6.7% rise, and the company said that the fourth quarter of 1991, which benefitted from the roll-out of new top-of-the-line models, was the unit’s strongest quarter ever, making the comparison for this year’s fourth quarter a tough one; analysts worry that the slowdown will spill over into related storage and software revenues.