The market structure

What is the market structure of this industry and why? You must analyze this real-world industry in relation to the characteristics of market structures to make this determination.
The characteristics of market structure that must be discussed are as follows:
How many competitors existed in this industry during this time period? Did it change during the time period?
What is the concentration ratio of this market? You should look at the beginning and the end of the time period. Concentration ratio as defined in economics is the market share of the largest 4 competitors added together. It is a key determinant of market structure and must be included.
What is the level of market power of your company of focus and the largest competitors? How does it change from the beginning of the time period to the end? Why?
What are the barrier to entry? Are these high barriers to entry or low barriers to entry? Why?
In part 1 you would have discussed whether the products were identical or differentiated. How does this impact brand loyalty of consumers?
Discuss any significant changes in any of these areas during the time period for analysis.