NYSE 60 trading day BetaEquityLM for Lockheed Martin = 0.37Debt/equity ratio for Lockheed Martin = 0.410Betaasset defense = 0.37/[1+(1-0.35)0.41] = 0.29S&P500 60 trading day BetaEquityNG for Northrop Grumman=0.30Debt/equity ratio for Northrop Grumman = 0.640Betaasset defense = 0.30/[1+(1-0.35)0.640 = 0.21Average beta of defense = 0.25