Regression and Machine learning models for panel data I have a panel data which consists of the sales of different companies across different years. Can someone tell me what kinds of regressiona and ML methods we use for forecasting the sales?

Thanks
Sales data is Time-series data. You should use the method of Time-series forecasting.

Below is a list of useful links to start with - 

Analytics Vidhya
Yashuseth blog
Kaggle blog

This is a good book to grasp the concepts - 
Forecasting: Principles and Practice

Also, do check this similar question.
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