title: pandas Int64 data type fails in the describe or quantile functions
body: <p>My pandas problem is with the use of the describe() function and pandas nullable integer data type, Int64 (or Int32).  I believe that I have a data problem but am lost on how to find the data causing the problem.  Alternatively, does pandas have a bug computing of percentile statistics?<br/></p>
  <p>I created a pandas dataframe using read_csv and specified some of the data as Int64 with the dtype parameter.   The data specified as Int64 are counts of people and would be integers except for missing values.  The dataset has 807130 rows.  The problem column in question has these attributes: <br/></p>
  <blockquote>
  <p>Series_Complete_65Plus                  807130 non-null  Int64<br/></p>
  </blockquote>
  <p>The problem occurs when I used the describe function to examine the values, I receive this error message: <br/></p>
  <blockquote>
  <p>TypeError: cannot safely cast non-equivalent object to int64<br/></p>
  </blockquote>
  <p>What is peculiar is that I can compute almost all the summary statistics as the describe() function does using the individual functions: count, mean, std, min, median, and max, but not the 25th and 75th percentiles.  The quantile function works for the median or 50th percentile but fails for the 25th and 75th percentiles.  Why would 50th percentile work but not the 25th &amp; 75th percentiles?<br/></p>
  <p>If I read the column Series_Complete_65Plus as a float, there is no problem.  The computed values for the count, mean, std, min, median, and max are equal at 7 digits for the Int64 and float versions.  Neither the Int64 nor the float version indicate there are any missing values.  I also checked for null values with the isnull() function and none are found.  <br/></p>
  <p>I have three other columns specified as Int64, but they are handled by the describe function. <br/></p>
  <p>The dataset is a Centers for Disease Control and Prevention public dataset available at<br/>
  <a href="https://data.cdc.gov/Vaccinations/COVID-19-Vaccinations-in-the-United-States-County/8xkx-amqh" rel="nofollow noreferrer">the CDC website</a><br/></p>
  <p>The dataset is updated daily and the number of rows will change.</p>