anchor.diff:  ### Parsing stock prices
   
   The Yahoo Finance web site provides daily stock prices in a CSV format that has the
  -following structure (you can find a larger example in the [`docs/MSFT.csv`](docs/MSFT.csv) file):
  +following structure (you can find a larger example in the [`docs/MSFT.csv`](../docs/MSFT.csv) file):
   
       Date,Open,High,Low,Close,Volume,Adj Close
       2012-01-27,29.45,29.53,29.17,29.23,44187700,29.23
  
positive.code: let mean = 
    airQuality.Data 
    |> Seq.map (fun row -> row.Ozone) 
    |> Seq.filter (fun elem -> not (System.Double.IsNaN(elem))) 
    |> Seq.average 
  
  (**
  
negative.code: If the header includes the name of one of the standard SI units, then the generated type
  returns values annotated with the appropriate unit. 
  
  In this section, we use a simple file [`docs/SmallTest.csv`](../docs/SmallTest.csv) which
  looks as follows:
  
      Name,  Distance (metre), Time (second)
  