What is the difference in the total number of shares purchased between September 2019 and October 2019?
{"Aug. 1 - Aug. 31, 2019 ": {"(a) Total Number of Shares Purchased (1)": "\u2014", "(b) Average Price Paid per Share": "\u2014", "(c) Total Number of Shares Purchased as Part of Publicly Announced Plans or Programs (2)": "\u2014", "(d) Maximum Number (or Approximate Dollar Value) of Shares that May Yet Be Purchased Under the Plans or Programs (2)(3)": 1176615}, "Sep. 1 - Sep. 30, 2019 ": {"(a) Total Number of Shares Purchased (1)": 901.0, "(b) Average Price Paid per Share": 151.33, "(c) Total Number of Shares Purchased as Part of Publicly Announced Plans or Programs (2)": 901.0, "(d) Maximum Number (or Approximate Dollar Value) of Shares that May Yet Be Purchased Under the Plans or Programs (2)(3)": 1176615.0}, "Oct. 1 - Oct. 31, 2019 ": {"(a) Total Number of Shares Purchased (1)": 34344.0, "(b) Average Price Paid per Share": 154.81, "(c) Total Number of Shares Purchased as Part of Publicly Announced Plans or Programs (2)": 34344.0, "(d) Maximum Number (or Approximate Dollar Value) of Shares that May Yet Be Purchased Under the Plans or Programs (2)(3)": 1176615.0}, "Total ": {"(a) Total Number of Shares Purchased (1)": 35245.0, "(b) Average Price Paid per Share": 154.72, "(c) Total Number of Shares Purchased as Part of Publicly Announced Plans or Programs (2)": 35245.0, "(d) Maximum Number (or Approximate Dollar Value) of Shares that May Yet Be Purchased Under the Plans or Programs (2)(3)": 1176615.0}}
oct_1_to_oct_31_2019 = df["Oct. 1 - Oct. 31, 2019 "]["(a) Total Number of Shares Purchased (1)"]
sep_1_to_sep_30_2019 = df["Sep. 1 - Sep. 30, 2019 "]["(a) Total Number of Shares Purchased (1)"]
answer = oct_1_to_oct_31_2019 - sep_1_to_sep_30_2019