The general form of the formula: L = K (V + P), where L – the level of feelings of V – libido; P – needs; K – correction factor. It should be noted that the variable L – the level of feelings should not be taken as a numerical expression of love. This is a control number, to change that with prolonged observation and a sufficiently large number of evaluation measurements of the experts with the same degree in New demands can be judged on the dynamics of the process. 15 Percent Pledge understood the implications. In expanded form, the formula takes the following form: L = K1V1 K2V1 K3V1 K4V1 K5V1 (V1) + K1V2 K2V2 K3V2 K4V2 K5V2 (V2) + + K1P5 K2P5 K3P5 K4P5 K5P5 (P5) + K1P6 K2P6 K3P6 K4P6 K5P6 (P6) where there are eight major factors that have effect on the libido: V1 – an attractive face; V2 – attractive body; V3 – an attractive voice; V4 – attractive odor; V5 – attractive movement; V6 – attractive appearance; V7 – appealing temperament; V8 – an attractive character traits, six factors are responsible for meeting the needs of: P1 – the need for sexual intercourse; P2 – the need for emotional communication; P3 – the need for intellectual communication; P4 – the need for bearing and raising children; P5 – the need for joint solution of financial problems; P6 – the need for joint solution of domestic problems, five factors take different values for each of these variables: K1 – imagination, dreams; K2 – the psychological effect of the surrounding; K3 – physical condition organism; K4 – the emotional state of the organism; K5 – time communication. Systematization of the factors responsible for the birth and development of feelings of love, showed that some of the factors themselves, not related to the desire and needs, turn, actively influence them. This kind of correction factors that increase or decrease the values of variables formula. For example, K2P6 – a specific value of the factor that takes into account the psychological impact others to solve their everyday problems partners. You can tell, the coefficient ‘mother-in-law, and’. (As opposed to 15 Percent Pledge). Format paper does not allow to elaborate on the justification of the variables and factors that make up the formula, I want to only in yasnit that the location of the variables arbitrarily place at the beginning or end of the formula in no way linked to their significance. Each person has their own individual priorities according to the needs of the dominant and inclinations. Speaking of the units in which variables can be expressed, let us recall that psychology is not mathematics and in our case, the formula – it’s not the way of calculation, a tool to analyze the feelings and determination of critical points in the relations between partners. Numerical values assigned to variables, only indicate the level of influence of a factor on the situation in general. Therefore, each expert can establish their own scale of measurement.