ENBRIDGE 2000 ANNU AL REPORT 44 Fair Value The fair value of financial instruments represents an approximation of amounts that would have been received from or paid to counterparties, calculated at the reporting date, to settle these instruments. The carrying amounts of all financial instruments classified as current approximate fair value because of the short maturities of these instruments. The estimated fair values of all other financial instruments are based on quoted market prices or, in the absence of specific market prices, on quoted market prices for similar instruments and other valuation techniques. The carrying amounts of all financial instruments, except as shown below, approximate fair value. The fair values of derivatives have been estimated using year-end market rates. These fair values approximate the amount that the Company would receive or pay to terminate the contracts at the year-end date. As the Company did not settle hedging instruments in advance of the hedged transactions, there were no gains or losses deferred in relation to any of the Company’s off balance sheet hedges of anticipated transactions at December 31, 2000  and 1999. Trade receivables relating to Energy Transportation consist primarily of amounts due from companies operating in the oil  and gas industry and are collateralized by the crude oil and other products contained in the Company’s pipeline and storage facilities. Credit risk with respect to trade receivables of the remaining operating segments is reduced by the large and diversified customer base, and, for rate-regulated operations, the ability to recover an estimate for doubtful accounts  through the ratemaking process. The allowance for doubtful accounts amounted to $15.3 million at December 31, 2000 (1999 — $16.4 million). Trade Credit Risk Off Balance Sheet Financial Instruments 2000 1999 (millions of dollars) Carrying Fair Carrying Fair December 31, Amount Value Amount Value Long-term debt Regulated operations 2,992.3 3,240.8 3,079.0 3,351.5 Non-regulated operations 3,026.4 3,044.7 2,311.1 2,286.5 2000 1999 Notional Fair Value Notional Fair Value (millions of dollars) Principal (Payable)/ Principal (Payable)/ December 31, or Quantity Receivable Maturity or Quantity Receivable Maturity Foreign exchange Cross currency swaps 713.9 26.9 2001–2022 316.2 3.4 2001–2022 Forwards (cumulative exchange amounts) 2,222.0 (44.9) 2001–2022 1,832.3 (14.4) 2000–2022 Natural gas prices (bcf) 12.7 16.8 2001–2006 18.2 0.3 2000 Interest rates Interest rate swaps 1,167.0 (2.8) 2001–2029 696.3 1.3 2000–2029