$1.$ You are a supply chain analyst for a company that manufactures and distributes solar$-$powered garden lights. Due to a rising interest in renewable energy products, sales have been steadily increasing. Your task is to forecast the next month's sales to ensure that production aligns with demand. $[15$ pts$]$

Monthly Sales Data $($in units$)$ for Solar$-$Powered Garden Lights $(2023)$

Month

Sales

January

$4000$

February

$4050$

March

$4100$

April

$4150$

May

$4200$

June

$4250$

July

$4300$

August

$4350$

September

$4400$

October

$4450$

November

$4500$

December

$4550$

a$.$ Using the Simple Exponential Smoothing method, forecast the sales for the next month $($January of the following year$)$ using alpha $=0\mathrm{.}1.$

Calculate and use the tracking signal to monitor the accuracy of the forecast. Comment on whether the forecast is performing well.

Hint: Tracking signal is based on historical data