Inhale. More Americans are assuming the lotus position. In fact, last year, 7.4 million Americans age 6 and older participated in yoga or tai chi classes, reports the Sporting Goods Manufacturers Association (SGMA), a 16 percent increase over participation rates in 1999, and a 30 percent increase over 1998 figures. Of those who practiced yoga or tai chi last year, 5.6 million, or 3 in 4, were female, according to the SGMA. Upon a closer investigation, the SGMA also discovered that the typical yoga or tai chi disciple is 40 years old, has an annual household income of $67,000 and has been practicing yoga for the past 4.5 years. On average, yoga devotees participate in their discipline about once a week, or 55 times a year. Now exhale.