will become the fourth women's service book to lower its rate base next year when it chops 400,000 copies from the rate base guarantee, lowering it 8.7% to 4.2 million, effective with the January issue. There will be no change in the ad rate; a color page remains $103,300, which means the cost per thousand is up 9.5%. Four other Gruner & Jahr USA Publishing magazines will boost their rate bases effective in February--YM
, up 100,000 to 2 million; Fitness
, up 100,000 to 700,000; Child
and American HomeStyle & Gardening
, up 75,000 apiece to hit 775,000. Family Circle
, which is boosting ad rates 10% while maintaining its rate base at 5 million, plans to raise its newsstand price 30% to $1.29.