roubles of capital Investment but 7 million roubles (2+5) which exceeds the volume of capital Investment of the second variant bY 751. Morever. the afore said 5 mil lion roubles have been neglected by the profitableness Indicator. Only additional cal­ culations make It possible to Identify the more capital-Intensive vrlant which originally seems to be less capital-Intensive. One may etlmlnate these calculations If during economic substantia• tlon of the variant we would use direct comparison of estimated payoff periods with the normative payoff period. In our example the additional capital Investment equals 2 million roubles and the prime cost reduction for the same output of produce- 0.6 million roubles. This shows that estimated payoff period will be 3.33 (2/0.6 } or twice as less as the payoff normative period 27-1 which equals 8.33 years (1/0.12). the second variant. This confirms efficiency of Thus, by using the Indicator of "payof( period" it becomes possible to Identify the most efficient variant of a project preparation decision. However this Indicator does not represent g en e r a I e ff I c I en c y o f c a p i t a I I n v e s t mei1 t b u t r a t h e r c om par a t I v e efficiency related directly to the indicator of annual reduced costs. This can be easily seen from making a simple transformation of the Initial formula used for selection of the best variant of capital investment by m1n1mum estimated payoff period. It Is possible to express our example in the following manner. Te = (12 -11)/(Cl -C2l Tn = 1 I En where Te and Tn denote the corresponding estimated and normative payoff period of additional capital invesment; En denotes a normative coefficient of capital efficiency; 
**Analysis**
The text discusses the evaluation of investment projects, specifically the comparison of two variants of capital investment, and the use of an indicator called "payoff period" to determine the most efficient project. The text also mentions the calculation of additional capital investment and prime cost reduction, which suggests that the focus is on the economic efficiency of the investment. Additionally, the text assumes a normative payoff period and a normative coefficient of capital efficiency, which implies a context of economic planning and decision-making.

**Category**
Industry, Science and technology