I am a programmer not much into math.
I have daily data of multiple products (total sales count and amount).
Manually we can see the anomaly in the count or amount like if there is a dip or hike in data by plotting them.
But now we have lots of products and can not track them manually. So now I am looking for a solution that can detect anomalies in each product.
Like in the below picture, the blue line shows the daily count of one product for the last 30 days.
I also tried to calculate the Exponentially weighted Average (orange line and added margin in gray line).
Then I get the data for the same product for the same weekdays. like if data is of if will get the data of Mondays.
then took the same exponentially weighted averages.
Then I created the 3rd graph by adding the weightages of both graphs. like took 30% from first value and 70% from the second.
But still, I am not sure if it will work fine.
Or if there are better ways to detect anomalies.
I hope if I was able to describe the actual problem.
Please try to be kind as I am very new to this and don't have much knowledge. Some useful articles will also be helpful thanks.