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Major improvements in the productivity of rice (Oryza sativa L.) and wheat (Triticum aestivum L.) have occurred in South Asia since 1965–1966 when the Green Revolution began. However, after the 1980s, yield stagnated or declined. We analyzed grain yield trends, soil C, N, P, and K status, and P and K balances in a 14‐yr rice–wheat experiment conducted at Punjab, India with 11 treatments comprised of various combinations of inorganic and organic sources of nutrients. Recommended levels of N, P, and K were supplemented with N through farmyard manure (FYM), wheat chopped straw (WCS), or sesbania (Sesbania cannabina Linn. & Merrill). Soil parameters were analyzed in archived soil samples collected periodically from 1988 to 1999. Rice yield declines ranged from 0.07 to 0.13 Mg ha⁻¹ yr⁻¹ dependent on treatment. Wheat yields declined by 0.04 Mg ha⁻¹ yr⁻¹ with applications of 75 and 100% N‐P‐K …