Net financial position (non-U.S. GAAP measure): resources (debt), represents the balance between our total liquidity and our total financial debt. Our total liquidity includes cash and cash equivalents, restricted cash, short-term deposits and marketable securities, and our total financial debt includes short-term borrowings, current portion of long-term debt and long-term debt, all as reported in our consolidated balance sheet. We believe our net financial position provides useful information for investors and management because it gives evidence of our global position either in terms of net indebtedness or net cash position by measuring our capital resources based on cash and cash equivalents, restricted cash, short-term deposits and marketable securities and the total level of our financial indebtedness.

(US$ m)	Dec 31 2019	Sep 28 2019	Jun 29 2019	Mar 30 2019	Dec 31 2018
Cash and cash equivalents	2,597	2,345	2,119	2,307	2,266
Restricted Cash	10	60	60	60	-
Short-term deposits	4	-	-	-	-
Marketable securities	133	133	333	331	330
Total liquidity	2,744	2,538	2,512	2,698	2,596
Short-term debt	(173)	(171)	(174)	(173)	(146)
Long-term debt	(1,899)	(2,019)	(2,030)	(2,015)	(1,764)
Total financial debt	(2,072)	(2,190)	(2,204)	(2,188)	(1,910)
Net financial position	672	348	308	510	686

Free cash flow (non-U.S. GAAP measure) is defined as net cash from operating activities minus net cash from (used in) investing activities, excluding payment for purchases (proceeds from matured) marketable securities and short-term deposits. We believe free cash flow provides useful information for investors and management because it measures our capacity to generate cash from our operating and investing activities to sustain our operating activities. Free cash flow does not represent total cash flow since it does not include the cash flows generated by or used in financing activities. In addition, our definition of free cash flow may differ from definitions used by other companies.