When dealing with a lying-ass motherfucker, the Lying-ass Motherfucker Coefficient (LAMC)is the multiplier (generally around .39) added to any numbers (such as income, number of recent sexual relations, cost of automobile, amount of alcohol consumed, length of prison sentence, etc) quoted by said lying-ass motherfucker, with the intent of approximating a truer estimate of the referenced events.

The actual value of the LAMC fluctuates depending on the relative purity of the lying-ass motherfucker in question and must be adjusted accordingly. A LAMC of .8 or .9 is only appropriate for a "part-time" or a "fly-by-night" lying-ass motherfucker, while a true, pathological lying-ass motherfucker often necessitates a .1 or even a .05!

Use a known quantity to assign a LAMC value to the lying-ass motherfuckers in your life. If, for instance, a lying ass motherfucker at your work claims he made a cool $120 in tips over the course of his shift when you spotted him pocketing a paltry $45, you can safely place his LAMC at .375, give or take a few hundredths.

Once a LAMC is established, it tends to remain fairly constant, varying only in cases of extreme mental excitement, anguish, or upheaval. Lying-ass motherfuckers who are manic drunks, for example, often require a lower LAMC value when they are on the sauce. Tears in the beer, however, can indicate that a higher value should be used ("in vino veritas" rings true, for depressive drunk lying-ass motherfuckers at least).

A final not...