 So, this is the 90th percentile concept which is seen in UCR system of payment and the Delta Dental Plan. So, in UCR, the payment will be at 90th percentile and 50th percentile for two group of dentists. So, let's see what is exactly the 90th percentile concept. So, I have a hypothetical scenario here. A test is being happened with the total number of students 100 and the maximum mark of that particular test is 100. So, I am keeping 100 and 100 and I am plotting into x-axis and y-axis. So x-axis is a percentage of students or the number of students both will be same because I kept 100. So, it is for the easier calculation. On the y-axis, it is a score. So, for that particular exam, Mr. x got the highest mark that is 95, he got the first place and Mr. y got the least mark that is 21 is the lowest mark. So, percentile by definition, it is a percentage of people who are coming under a particular value. If it is 90th percentile means, 90 percentage of observations will be under that particular value. So, this will be always a value. So, it will be always a particular value. So, 90th percentile is nothing but 90 percentage of the observation coming under that particular value. So, let us get back to our example. So, the highest we got for Mr. x that is 95. That means all the students that is 100 students got marks 95 or lesser, right? So, 95 is a 100th percentile because the maximum score is 95, beyond 95 there is no student got marks. So, all the students got marks 95 or lesser. So, the least person got 21 mark and there is no person less than 21. So, the zero percentile is 21. So, usually zero percentile will not be calculated, but just for your understanding. So, 95 is a 100th percentile and 21 is a zero percentile. Now, you will be having a good idea about what is percentile. So, what is 90th percentile? Nineteenth percentile is the value under which 90 percentage of the observation lies. That means, 90 percentage of the students or 90 students will be having. They will be having value under a particular score. So, how to calculate that? We put all the students value or the scores in ascending order, okay? From the lowest Mr. y to Mr. x highest, 21 to 95. So, it goes in a increasing fashion. So, this is 100 percentage and 100 percentile is 95, zero percentile is 21. So, let's see what is the score at 90th percentage. So, 90 students will be having one score. That means, that particular score is of that 90th student on an increasing fashion. Below that, there will be 90 students. So, suppose we get the score of 83. 83 is the score under which 90 students marks lies. So, beyond 83, there will be 10 people and equal or less than 83, there will be 90 people, okay? So, 83 to 95, there will be 10 people. So, now we can calculate 80, 70, 60, 50. So, each data set, this course will change. This is just a hypothetical example. So, 90 percentile is 83. So, I am putting here percentage just for understanding if the number and this score is different. The entire calculation will be changed. So, only thing you have to calculate the percentage. So, this is 83 where 90 percentage of the or 90 students having marks lesser or equal. 80 percentage is 71. So, 71 is the score where we having 80 students marks lesser or equal and 50 percentage is 44. So, these scores are the percentiles. So, this is 100 percentile. 83 is the 90th percentile. 100 percentile is 95. 71 is the 80th percentile and 44 is the 50th percentile. So, how do we get these value? It is just calculating by putting it in an increasing order and just see 50 students where the marks are coming, 60 students where the marks are coming, 70, 80, 90 like that. So, if we have a different number we need to calculate the percentage and see where exactly that particular score is coming. So, that is the 90th percentile concept. So, it is very easy only thing. This is a hypothetical example. X and Y axis I have put 100 and 100, 100 students and 100 marks. So, only thing if you have 200 and again 200. Only thing you have to calculate the percentage and see where exactly the value is coming. So, in UCR concept the participating dentists will be getting 90th percentile and non-participating will be getting 50th percentile.