1. To understand if demand for a customer segment is changing over time the company tracked historical demand for one of its products as follows:

Demand Demand

April		60			July	60
May		55			August	80
June		75			September	75

1. Using simple linear regression, calculate the trend line for the historical data. Let's say the X axis is April=1, May=2, and so on, while the Y axis is demand.
2. Calculate a forecast for October using your regression formula.