[01] P. N. Brusov, Applied Mathematics Department, Financial University under the Government of Russian Federation, Moscow, Russia. [02] T. V. Filatova, Dean of GMM Faculty, Financial University under the Government of Russian Federation, Moscow, Russia. [03] N. P. Orekhova, High School of Business, Southern Federal University, Investment and Taxation Laboratory, Research Consortium of Universities of the South of Russia, Rostov-on-Don, Russia. [04] A. P. Brusova, Management Department, Financial University under the Government of Russian Federation, Moscow, Russia. [05] V. L. Kulik, Management Department, Financial University under the Government of Russian Federation, Moscow, Russia.

In this paper developed by the authors models of evaluation of the dependence of effectiveness of investments on debt financing are applied for the analysis of investments of one of the biggest telecommunication company of Russia for 2010-2012 years from the point of view of optimal structure of investment. The analysis revealed, that only in 2011 the company's investment structure was close to the optimal.

Investment Projects with Arbitrary Duration, Effectiveness of Investment Project, Optimal Leverage Level, Taxes Impact

[01] Brusov P, Filatova T, Orehova N, Eskindarov M (2015), Modern corporate finance, investments and taxation, Springer International Publishing, Switzerland, 373 p. [02] Brusov P, Filatova T, Orehova N, Brusova A (2011a) Weighted average cost of capital in the theory of Modigliani–Miller, modified for a finite life–time company. Applied Financial Economics 21(11): 815-824 [03] Brusov P, Filatova P, Orekhova N (2013a) Absence of an Optimal Capital Structure in the Famous Tradeoff Theory! Journal of Reviews on Global Economics 2: 94-116 [04] Brusov P, Filatova P, Orekhova N (2014a) Mechanism of formation of the company optimal capital structure, different from suggested by trade off theory. Cogent Economics & Finance 2: 1-13 http://dx.doi.org/10.1080/23322039.2014.946150 [05] Brusov P, Filatova T, Orehova N et al. (2011b) From Modigliani–Miller to general theory of capital cost and capital structure of the company. Research Journal of Economics, Business and ICT 2: 16–21 [06] Brusov P, Filatova T, Eskindarov M, Orehova N (2012a) Influence of debt financing on the effectiveness of the finite duration investment project. Applied Financial Economics 22 (13) : 1043-1052 [07] Brusov P, Filatova T, Orehova N et al (2011c) Influence of debt financing on the effectiveness of the investment project within the Modigliani–Miller theory. Research Journal of Economics, Business and ICT (UK) 2: 11-15 [08] Brusov P, Filatova T, Eskindarov M, Orehova N (2012b) Hidden global causes of the global financial crisis. Journal of Reviews on Global Economics 1: 106-111 [09] Brusov P, Filatova T, Orekhova N (2013b) Absence of an Optimal Capital Structure in the Famous Tradeoff Theory! Journal of Reviews on Global Economics 2: 94–116 [10] Brusov P.N., Filatova Т. V. (2011d) From Modigliani–Miller to general theory of capital cost and capital structure of the company. Finance and credit 435: 2–8. [11] Brusov P Filatova T Orehova N Brusov P.P Brusova N. (2011e) From Modigliani–Miller to general theory of capital cost and capital structure of the company. Research Journal of Economics, Business and ICT 2: 16–21 [12] Brusov P Filatova T Orehova N (2014b) Inflation in Brusov–Filatova–Orekhova Theory and in its Perpetuity Limit – Modigliani – Miller Theory. Journal of Reviews on Global Economics 3: 175-185 [13] Brusov P Filatova T Orehova N (2013c) A Qualitatively New Effect in Corporative Finance: Abnormal Dependence of Cost of Equity of Company on Leverage. Journal of Reviews on Global Economics 2: 183-193 [14] Filatova Т Orehova N Brusova А (2008) Weighted average cost of capital in the theory of Modigliani–Miller, modified for a finite life–time company. Bulletin of the FU 48: 68–77 [15] Brusova A (2011) А Comparison of the three methods of estimation of weighted average cost of capital and equity cost of company. Financial analysis: problems and solutions 34 (76): 36-42 [16] Мodigliani F, Мiller M (1958) The Cost of Capital, Corporate Finance, and the Theory of Investment. American Economic Review 48: 261–297 [17] Мodigliani F, Мiller M (1963) Corporate Income Taxes and the Cost of Capital: A Correction. American Economic Review 53: 147–175 [18] Modigliani F, Miller M (1966) Some estimates of the Cost of Capital to the Electric Utility Industry 1954–1957 . American Economic Review 56: 333-391