With the increasing competition in the telecommunications industry, the operators try their best to increase
telecom income via various measures, one of which is to set an amount of income as a goal to make the encouragement.
Since accurate forecast of income plays an important role in income target setting, this paper builds a time series Autoregressive
Integrated Moving Average Model (ARIMA) based on the analysis of income data. Two important issues are involved
when setting up the ARIMA model: first, smooth the old data and identify the model, and then estimate the parameters
in the model by SPSS software. As a result, we set up an ARIMA (1,2,1) model with order 1 auto-regression, order
2 difference and order 1 lag. Finally, computer simulations are made based on the real data from a telecommunication
company and experimental results show that the proposed model fits income data well and performs well in forecasting.