Excluding the one-time gain in relation to the receipt of the 33% equity interest in Ant Group for the six months ended September 30, 2019, share-based compensation expense, revaluation and disposal gains/losses of investments, impairment of investments and goodwill and certain other items, non-GAAP net income for the six months ended September 30, 2020 was RMB86,562 million (US$12,749 million), an increase of 36% compared to RMB63,699 million for the same period of 2019. A reconciliation of net income to non-GAAP net income is included at the end of this document.
Net income attributable to ordinary shareholders
Net income attributable to ordinary shareholders for the six months ended September 30, 2020 was RMB76,360 million (US$11,247 million), a decrease of 19% compared to RMB93,792 million for the same period of 2019, when we booked a significant one-time gain upon the receipt of the 33% equity interest in Ant Group. The increase in share-based compensation expense related to Ant Group share-based awards granted to our employees also contributed to the year-over-year decrease in net income attributable to ordinary shareholders, which was partly offset by a net gain arising from changes in the fair value of our equity investments for the six months ended September 30, 2020, as well as impairment charges relating to our equity method investees for the six months ended September 30, 2019.
Diluted earnings per ADS/share and non-GAAP diluted earnings per ADS/share
Diluted earnings per ADS for the six months ended September 30, 2020 was RMB27.83 (US$4.10) on a weighted average of 21,943 million diluted shares outstanding during the period, a decrease of 22% compared to RMB35.58 on a weighted average of 21,084 million diluted shares outstanding during the same period in 2019. Excluding the one-time gain in relation to the receipt of the 33% equity interest in Ant Group for the six months ended September 30, 2019, share-based compensation expense, revaluation and disposal gains/losses of investments, impairment of investments and goodwill and certain other items, non-GAAP diluted earnings per ADS for the six months ended September 30, 2020 was RMB32.79 (US$4.83), an increase of 28% compared to RMB25.65 for the same period of 2019.
Diluted earnings per share for the six months ended September 30, 2020 was RMB3.48 (US$0.51 or HK$3.96), a decrease of 22% compared to RMB4.45 for the same period of 2019. Excluding the one-time gain in relation to the receipt of the 33% equity interest in Ant Group for the six months ended September 30, 2019, share-based compensation expense, revaluation and disposal gains/ losses of investments, impairment of investments and goodwill and certain other items, non-GAAP diluted earnings per share for the six months ended September 30, 2020 was RMB4.10 (US$0.60 or HK$4.67), an increase of 28%, compared to RMB3.21 for the same period of 2019.
A reconciliation of diluted earnings per ADS/share to non-GAAP diluted earnings per ADS/share is included at the end of this document. Each ADS represents eight ordinary shares, which reflects the share subdivision and ADS ratio change that became effective on July 30, 2019.
Cash, cash equivalents and short-term investments
As of September 30, 2020, cash, cash equivalents and short-term investments were RMB405,912 million (US$59,784 million), compared to RMB358,981 million as of March 31, 2020. The increase in cash, cash equivalents and short-term investments for the six months ended September 30, 2020 was primarily due to free cash flow generated from operations of RMB77,110 million (US$11,357 million), partly offset by cash used in investment and acquisition activities of RMB30,863 million (US$4,546 million).