Reasons for sustained, high levels of spending out-of-pocket are unclear. Part of the reason may be dissatisfaction with the quality or accessibility of services provided by institutions to which individuals are affiliated, leading them to seek care from private health providers. Nearly three in ten Mexicans die within a month of a heart-attack (and this rate is worsening), compared to less than one in ten across the OECD on average (where survival rates are generally improving).