What is the change in the number of total services subscribers in 2019?
{"Wireless subscribers [1][2]": {"2019": 9957962.0, "2018": 9610482.0, "% CHANGE": 3.6}, "Postpaid [1][2]": {"2019": 9159940.0, "2018": 8830216.0, "% CHANGE": 3.7}, "Prepaid [1]": {"2019": 798022.0, "2018": 780266.0, "% CHANGE": 2.3}, "Retail high-speed Internet subscribers [1][3]": {"2019": 3555601.0, "2018": 3410374.0, "% CHANGE": 4.3}, "Retail TV subscribers [3]": {"2019": 2772464.0, "2018": 2766411.0, "% CHANGE": 0.2}, "IPTV": {"2019": 1767182.0, "2018": 1675706.0, "% CHANGE": 5.5}, "Satellite": {"2019": 1005282.0, "2018": 1090705.0, "% CHANGE": -7.8}, "Total growth services subscribers": {"2019": 16286027.0, "2018": 15787267.0, "% CHANGE": 3.2}, "Wireline retail residential NAS lines [3]": {"2019": 2697483.0, "2018": 2960808.0, "% CHANGE": -8.9}, "Total services subscribers": {"2019": 18983510.0, "2018": 18748075.0, "% CHANGE": 1.3}}
total_services_subscribers_2019 = df["Total services subscribers"]["2019"]
total_services_subscribers_2018 = df["Total services subscribers"]["2018"]
answer = total_services_subscribers_2019 - total_services_subscribers_2018