# Monitoring of Time and Cost Variances of Schedule Using Simple Earned Value Method Indicators
## 3 Results: Application of T/S and T/C Monitoring  
T/S and T/C monitoring of variances arising during the implementation of the works covered by the schedule, was divided into three scenarios of its implementation, according to the methods adopted above. The adopted calculation models are characterized by a 10%  
Figure 3: Cumulative values of planned costs (BCWS) of schedules-in implementation methods according to steady (dot chart), parallel (continuous chart), sequence (intermittent chart) execution of works. Source: [19]. increase in the budget of costs (C = 110%, 120%, 130%, and 140%) and a 5% increase in the time of works execution (S = 105%, 110%, 115%, and 120%), respectively. These models are described with symbols A1B1 \(\div\) A4B4, indicating the increase in variances [8]. For T/S monitoring, the impact of the increasing delay parameter (A models) was adopted, while for T/C monitoring the impact of delays and cost overruns combined (AB models). The steady execution method assumes a global (overall) impact of variances (A, B)-for all schedule processes. In the methods of parallel and sequence work execution, the local (partial) impact of variances (a, b) was adopted-on selected process sequences. This is due to the obvious characteristics of these methods, widely described in the literature (delays of the analyzed process sequences do not always affect the delays of their successors). The analysis of the growth rate of unplanned costs and the work performance deviating from the plan consists in a gradual increase in expenditure on production (C), with a simultaneous systematic reduction of the production rate (S). These phenomena are reflected in the lowering of the value of simple indicators of the earned value method: pool of actual costs (ACWP) and earned value index (BCWP), which determine the monotonicity of the T/S and T/C monitoring indicators. The results of the analysis for the parallel execution method, with a description of the introduced time and cost disturbances and the division into four variances scenarios, are presented in Table 1.  
\begin{table}
\begin{tabular}{c c c c c} \hline \hline \begin{tabular}{c} **Registration** \\ **Stage/Variance** \\ **Scenario** \\ \end{tabular}  & \begin{tabular}{c} **BCWP** \\ **BCWS** \\ **ACWP** \\ **(PLN)** \\ \end{tabular}  & \begin{tabular}{c} **BCWP-BCWS** \\ **(PLN)** \\ \end{tabular}  & \ \begin{tabular}{c} **BCWP-ACWP** \\ **(PLN)** \\ \end{tabular}  & \begin{tabular}{c} **T/C** \\ **T/S** \\ **(–)** \\ \end{tabular}  \\ \hline \hline \multicolumn{5}{c}{Models a1(II): s = 100\%, c = 110\% (for T/S)//alb1(II): s = 105\%, c = 110\% (for T/C)} \\ \hline \multirow{3}{*}{31.03.2017} & 736.965,50 & \multirow{3}{*}{0.00} & \multirow{3}{*}{0.00} & 0.000 \\  & 736.965,50 & & & \\ \hline \multirow{3}{*}{30.04.2017} & 2.578.038,90 & \multirow{3}{*}{\(-\)29.918,27} & \multirow{3}{*}{\(-\)97.036,77} & 0.647 \\  & 2.607.957,17 & & & \(-\)27.65 \\ \cline{1-1}  & 2.675.075,67 & & & \\ \hline \multirow{3}{*}{31.05.2017} & 5.249.292,03 & \multirow{3}{*}{\(-\)68.492,99} & \multirow{3}{*}{\(-\)208.625,09} & 0.672 \\  & 5.317.785,02 & & & \(-\)42.39 \\ \cline{1-1}  & 5.457.917,12 & & & \\ \hline \multirow{3}{*}{30.06.2017