Since the early 1980s, the Consumer Product Safety Commission has conducted a grim census, tracking reports of deaths from crashes of all-terrain vehicles, or ATVs. Now the body count has risen above 15,250, according to the agency’s latest annual report, with more than one in five of the deaths suffered by children under 16. The annual death count, which has sometimes exceeded 800, has mostly ranged from 550 to 650 in recent years. That seems like progress, but may actually be the result of riders switching to another type of off-road vehicle, called an ROV, that isn’t included in the ATV fatality reports. “The problem has not been solved,” said Rachel Weintraub, general counsel of the Consumer Federation of America (CFA).