mx is the central rate of mortality, defined as the number of deaths at age x last birthday in the three year period to which the Interim Life Table relates divided by the average population at that age over the same period.
	qx is the mortality rate between age x and (x +1), that is the probability that a person aged x exact will die before reaching age (x +1).
	lx is the number of survivors to exact age x of 100,000 live births of the same sex who are assumed to be subject throughout their lives to the mortality rates experienced in the three year period to which the Interim Life Table relates.
	dx is the number dying between exact age x and (x+1) described similarly to lx, that is dx = lx -lx+1.
	ex is the average expectation of life at exact age x, that is the average number of years that those aged x exact will live thereafter.