In 2018, in line with the commitment to strengthen its financial structure, the Group continued to implement various measures that enabled the reduction of debt and improvement of the Group’s credit rating outlook (Moody’s has improved its credit rating from BAA2 to BAA1, while Fitch and Standard & Poor’s improved the outlook from stable to positive).
In line with the financial prudence policy and the commitment to maintain a high level of liquidity, the liquid resources held by the Group at the end of the reporting period, in the form of cash and available credit lines, far exceed short-term debt maturities.
Net debt at the end of the reporting period is 3.439 billion euros, much lower than it was on December 31, 2017 (6.267 billion euros), mainly as a result of the significant cash flow generated by the businesses and by the divestment in Naturgy.
The Group's liquidity on December 31, 2018, including committed and unused credit lines, was at 8.742 billion euros, enough to cover the short-term debt maturities 2.33 times. Repsol had unused credit lines in the amount of 2.265 and 2.503 billion euros on December 31, 2018 and 2017, respectively.
Average period of payment to suppliers
The average period of payment to suppliers of the Group's Spanish companies in 2018 was 23 days, lower than the maximum legal period of 60 days established by Law 15/2010 of July 5 (amended by second final provision of Law 31/2014) on combating late payment in commercial transactions.
(1) Includes dividends collected, other payments for operating activities and the effect of the exchange rate.