Investing Activities. Cash used in investing activities was $1.0 million during FY 2021, as compared to $10.5 million used during FY 2020, resulting in a net increase in cash used between the periods of $9.5 million. Purchases of property, plant and equipment, or rolling stock (maintenance capital expenditures), were $1.2 million in FY 2021 as compared to $3.4 million in FY 2020, a decrease of $2.2 million in primarily our North American leasing operations. In both periods, proceeds from sales of property, plant and equipment were not significant. Net capital expenditures of lease fleet (purchases, net of proceeds from sales of lease fleet) were a negative $0.2 million in FY 2021, as compared to $7.3 million in FY 2020, a decrease of $7.5 million in net fleet investment. In FY 2021, net capital expenditures of lease fleet were approximately $1.9 million in North America, as compared to $8.1 million in FY 2020, a decrease of $6.2 million; and net capital expenditures of lease fleet in the Asia Pacific totaled a negative $2.1 million in FY 2021, versus a negative $0.8 million in FY 2020, a decrease of $1.3 million in net fleet investment. The amount of cash that we use during any period in investing activities is almost entirely within management’s discretion and we have no significant long-term contracts or other arrangements pursuant to which we may be required to purchase at a certain price or a minimum amount of goods or services.
Financing Activities. Cash used in financing activities was $10.5 million during FY 2021, as compared to only $0.5 million of cash used during FY 2020, a decrease to cash between the periods of $10.0 million. In FY 2021, we repaid a net $9.7 million on our equipment financing, senior and other debt versus borrowing a net $0.4 million in FY 2020. These financing activities were primarily to fund our investment in the container lease fleet, make business acquisitions, pay dividends on our preferred stock, repurchase shares of our common stock and manage our operating assets and liabilities. Cash of $0.9 million was used during both periods to pay dividends on primarily our Series C Preferred Stock and we received proceeds of approximately $0.1 million during both periods from issuances of common stock on exercises of stock options.
Asset Management
Receivables and inventories were $42.2 million and $20.2 million at September 30, 2020 and $44.1 million and $20.9 million at June 30, 2020, respectively. At September 30, 2020, DSO in trade receivables were 37 days and 42 days in the Asia-Pacific area and our North American leasing operations, as compared to 43 days and 40 days at June 30, 2020, respectively. Effective asset management is always a significant focus as we strive to apply appropriate credit and collection controls and maintain proper inventory levels to enhance cash flow and profitability. As further discussed above in “COVID-19,” if our customers experience adverse business consequences due to the COVID-19 pandemic, including being required to shut down their operations, demand for our services and products could also be materially adversely affected in a rapid manner, including the increase of DSO in trade receivables.
The net book value of our total lease fleet was $459.1 million at September 30, 2020, as compared to $458.7 million at June 30, 2020. At September 30, 2020, we had 99,844 units (23,711 units in retail operations in Australia, 8,972 units in national account group operations in Australia, 12,154 units in New Zealand, which are considered retail; and 55,007 units in North America) in our lease fleet, as compared to 100,645 units (24,147 units in retail operations in Australia, 8,946 units in national account group operations in Australia, 12,370 units in New Zealand, which are considered retail; and 55,182 units in North America) at June 30, 2020. At those dates, 75,460 units (19,288 units in retail operations in Australia, 5,983 units in national account group operations in Australia, 9,717 units in New Zealand, which are considered retail; and 40,472 units in North America); and 72,983 units (19,505 units in retail operations in Australia, 5,255 units in national account group operations in Australia, 10,149 units in New Zealand, which are considered retail; and 38,074 units in North America) were on lease, respectively.
In the Asia-Pacific area, the lease fleet was comprised of 37,809 storage and freight containers and 7,028 portable building containers at September 30, 2020; and 38,317 storage and freight containers and 7,146 portable building containers at June 30, 2020. At those dates, units on lease were comprised of 30,291 storage and freight containers and 4,697 portable building containers; and 29,839 storage and freight containers and 5,070 portable building containers, respectively.
In North America, the lease fleet was comprised of 38,903 storage containers, 6,496 office containers (GLOs), 4,193 portable liquid storage tank containers, 4,246 mobile offices and 1,169 modular units at September 30, 2020; and 39,169 storage containers, 6,355 office containers (GLOs), 4,194 portable liquid storage tank containers, 4,291 mobile offices and 1,173 modular units at June 30, 2020. At those dates, units on lease were comprised of 29,614 storage containers, 5,391 office containers (GLOs), 1,047 portable liquid storage tank containers, 3,452 mobile offices and 968 modular units; and 27,472 storage containers, 5,184 office containers (GLOs), 1,000 portable liquid storage tank containers, 3,474 mobile offices and 944 modular units, respectively.