General Electric ( GE) provided a marginally more upbeat forecast Monday than it gave analysts three weeks ago, saying volume in its disparate business lines is trending higher and prices starting to firm. The conglomerate also affirmed previous earnings estimates of $1.51 a share for 2002 and $1.55 to $1.70 a share in 2003. It said 12 of its 13 business lines are likely to show double-digit growth next year. Still, while the company's businesses are stabilizing, they so far lack a "spark" that would justify higher earnings guidance, GE said in a Web-based slide presentation ahead of an analyst call Tuesday morning by CEO Jeff Immelt. The company expects a big slowdown in the growth of its power systems unit, but a 20% surge in operating profit at NBC. GE's shares closed up 93 cents, or 3.7%, to $26.43 Monday.