Estimates of Pakistan's stockpile of nuclear warheads vary. The most recent analysis, published in the Bulletin of the Atomic Scientists in 2010, estimates that Pakistan has 70–90 nuclear warheads. In 2001, the US-based Natural Resources Defense Council (NRDC) estimated that Pakistan had built 24–48 HEU-based nuclear warheads with HEU reserves for 30–52 additional warheads. In 2003, the US Navy Center for Contemporary Conflict estimated that Pakistan possessed between 35 and 95 nuclear warheads, with a median of 60. In 2003, the Carnegie Endowment for International Peace estimated a stockpile of approximately 50 weapons. By contrast, in 2000, US military and intelligence sources estimated that Pakistan's nuclear arsenal may be as large as 100 warheads. In 2018, the Federation of American Scientists estimated that the arsenal was about 120-130 warheads.