Puts cost more so that is factored into the price. ex. SPY @170.9 AUG 16 166 P costs 0.23 (4.9 otm) 175 C costs 0.12 (4.1 otm)
Just for fun, here are some quick SPY stats. They are the percent changes from 3rd Fridays for the last 10 years. If doing Condors, keep in mind the marked, greater-than-5% moves: Code: Third Friday to third Friday changes (at Close) for SPY Start 20030919 Price: 103.67 20031017, 104.26, %Chg: 0.07 20031121, 104.21, %Chg: -0.05 20031219, 108.89, %Chg: 4.49 20040116, 114.23, %Chg: 4.90 20040220, 114.88, %Chg: 0.57 20040319, 111.06, %Chg: -3.33 20040416, 113.83, %Chg: 2.49 20040521, 109.81, %Chg: -3.53 20040618, 113.63, %Chg: 3.48 20040716, 110.70, %Chg: -2.58 20040820, 110.47, %Chg: -0.21 20040917, 113.15, %Chg: 2.43 20041015, 111.26, %Chg: -1.67 20041119, 117.42, %Chg: [b][color=Blue]5.54[/color][/b] 20041217, 119.44, %Chg: 1.72 20050121, 116.78, %Chg: -2.23 20050218, 120.38, %Chg: 3.08 20050318, 118.53, %Chg: -1.54 20050415, 114.15, %Chg: -3.70 20050520, 119.12, %Chg: 4.35 20050617, 121.36, %Chg: 1.88 20050715, 122.84, %Chg: 1.22 20050819, 122.46, %Chg: -0.31 20050916, 123.50, %Chg: 0.85 20051021, 118.12, %Chg: -4.36 20051118, 125.13, %Chg: [b][color=Blue]5.93[/color][/b] 20051216, 126.35, %Chg: 0.97 20060120, 125.96, %Chg: -0.31 20060217, 128.81, %Chg: 2.26 20060317, 130.62, %Chg: 1.41 20060421, 131.15, %Chg: 0.41 20060519, 127.10, %Chg: -3.09 20060616, 124.65, %Chg: -1.93 20060721, 123.94, %Chg: -0.57 20060818, 130.69, %Chg: [b][color=Blue]5.45[/color][/b] 20060915, 131.95, %Chg: 0.96 20061020, 136.84, %Chg: 3.71 20061117, 140.42, %Chg: 2.62 20061215, 142.34, %Chg: 1.37 20070119, 142.82, %Chg: 0.34 20070216, 145.73, %Chg: 2.04 20070316, 138.53, %Chg: -4.94 20070420, 148.62, %Chg: [b][color=Blue]7.28[/color][/b] 20070518, 152.62, %Chg: 2.69 20070615, 153.06, %Chg: 0.29 20070720, 153.50, %Chg: 0.29 20070817, 144.71, %Chg: [b][color=Red]-5.73[/color][/b] 20070921, 151.97, %Chg: [b][color=Blue]5.02[/color][/b] 20071019, 149.67, %Chg: -1.51 20071116, 145.79, %Chg: -2.59 20071221, 148.13, %Chg: 1.61 20080118, 132.05, %Chg: [b][color=Red]-10.86[/color][/b] 20080215, 135.14, %Chg: 2.34 20080320, 132.07, %Chg: -2.27 20080418, 138.48, %Chg: 4.85 20080516, 142.66, %Chg: 3.02 20080620, 131.57, %Chg: [b][color=Red]-7.77[/color][/b] 20080718, 125.97, %Chg: -4.26 20080815, 130.16, %Chg: 3.33 20080919, 124.11, %Chg: -4.65 20081017, 93.20, %Chg: [b][color=Red]-24.91[/color][/b] 20081121, 79.52, %Chg: [b][color=Red]-14.68[/color][/b] 20081219, 88.19, %Chg: [b][color=Blue]10.90[/color][/b] 20090116, 85.06, %Chg: -3.55 20090220, 77.42, %Chg: [b][color=Red]-8.98[/color][/b] 20090320, 76.71, %Chg: -0.92 20090417, 87.08, %Chg: [b][color=Blue]13.52[/color][/b] 20090515, 88.71, %Chg: 1.87 20090619, 92.04, %Chg: 3.75 20090717, 94.13, %Chg: 2.27 20090821, 102.96, %Chg: [b][color=Blue]9.38[/color][/b] 20090918, 106.71, %Chg: 3.64 20091016, 108.88, %Chg: 2.03 20091120, 109.43, %Chg: 0.51 20091218, 110.21, %Chg: 0.71 20100115, 113.64, %Chg: 3.11 20100219, 111.14, %Chg: -2.20 20100319, 115.97, %Chg: 4.35 20100416, 119.36, %Chg: 2.92 20100521, 109.12, %Chg: [b][color=Red]-8.58[/color][/b] 20100618, 111.73, %Chg: 2.39 20100716, 106.65, %Chg: -4.55 20100820, 107.53, %Chg: 0.83 20100917, 112.48, %Chg: 4.60 20101015, 117.70, %Chg: 4.64 20101119, 120.28, %Chg: 2.19 20101217, 124.30, %Chg: 3.34 20110121, 128.37, %Chg: 3.27 20110218, 134.53, %Chg: 4.80 20110318, 127.76, %Chg: [b][color=Red]-5.03[/color][/b] 20110415, 132.04, %Chg: 3.35 20110520, 133.61, %Chg: 1.19 20110617, 127.05, %Chg: -4.91 20110715, 131.69, %Chg: 3.65 20110819, 112.64, %Chg: [b][color=Red]-14.47[/color][/b] 20110916, 121.52, %Chg: [b][color=Blue]7.88[/color][/b] 20111021, 123.97, %Chg: 2.02 20111118, 121.98, %Chg: -1.61 20111216, 121.59, %Chg: -0.32 20120120, 131.54, %Chg: [b][color=Blue]8.18[/color][/b] 20120217, 136.41, %Chg: 3.70 20120316, 140.30, %Chg: 2.85 20120420, 137.95, %Chg: -1.67 20120518, 129.74, %Chg: [b][color=Red]-5.95[/color][/b] 20120615, 134.14, %Chg: 3.39 20120720, 136.47, %Chg: 1.74 20120817, 142.18, %Chg: 4.18 20120921, 145.87, %Chg: 2.60 20121019, 143.39, %Chg: -1.70 20121116, 136.37, %Chg: -4.90 20121221, 142.79, %Chg: 4.71 20130118, 148.33, %Chg: 3.88 20130215, 152.11, %Chg: 2.55 20130315, 155.83, %Chg: 2.45 20130419, 155.48, %Chg: -0.22 20130517, 166.94, %Chg: [b][color=Blue]7.37[/color][/b] 20130621, 159.07, %Chg: -4.71 20130719, 169.17, %Chg: [b][color=Blue]6.35[/color][/b] TOTAL MONTHS = 118 DOWN MONTHS = 43 UP MONTHS = 75 %UP MONTHS = 63.56% AVG %UP MONTH = 3.36% %DOWN MONTHS = 36.44% AVG %DOWN MONTH = -4.37%
Equivalent. But In general, I would be a buyer of puts over calls. Less risk of buy ins on hedging or dividend raises. I would be a seller of calls over puts for the same reason.
Here's some more you might find interesting. This is the last 50 years of 3rd Friday closes for SPX. I know it is not SET values, but I believe the stats are still significant for anybody doing a monthly SPY/SPX strategy. Note that over the last 50 years SPX is up month-month 60% of the time. I bet someone who is patient could develop and trade a system based on this... Code: Third Friday to third Friday changes (at Close) for SP-500 Start 19620216 Price: 70.59 19620316, 70.96, %Chg: 0.31 19620419, 68.59, %Chg: -3.34 19620518, 63.82, %Chg: [b][color=Red]-6.95[/color][/b] 19620615, 55.89, %Chg: [b][color=Red]-12.43[/color][/b] 19620720, 56.81, %Chg: 1.65 19620817, 59.01, %Chg: 3.87 19620921, 57.69, %Chg: -2.24 19621019, 55.59, %Chg: -3.64 19621116, 60.16, %Chg: [b][color=Blue]8.22[/color][/b] 19621221, 62.64, %Chg: 4.12 19630118, 65.18, %Chg: 4.05 19630215, 66.41, %Chg: 1.89 19630315, 65.93, %Chg: -0.72 19630419, 69.23, %Chg: [b][color=Blue]5.01[/color][/b] 19630517, 70.29, %Chg: 1.53 19630621, 70.25, %Chg: -0.06 19630719, 68.35, %Chg: -2.70 19630816, 71.49, %Chg: 4.59 19630920, 73.30, %Chg: 2.53 19631018, 73.32, %Chg: 0.03 19631115, 72.35, %Chg: -1.32 19631220, 74.28, %Chg: 2.67 19640117, 76.56, %Chg: 3.07 19640320, 78.92, %Chg: 3.08 19640417, 80.55, %Chg: 2.07 19640515, 80.61, %Chg: 0.07 19640619, 80.89, %Chg: 0.35 19640717, 84.01, %Chg: 3.86 19640821, 82.07, %Chg: -2.31 19640918, 83.48, %Chg: 1.72 19641016, 84.83, %Chg: 1.62 19641120, 86.28, %Chg: 1.71 19641218, 84.29, %Chg: -2.31 ... 20100115, 1,136.03, %Chg: 3.04 20100219, 1,109.17, %Chg: -2.36 20100319, 1,159.90, %Chg: 4.57 20100416, 1,192.13, %Chg: 2.78 20100521, 1,087.69, %Chg: [b][color=Red]-8.76[/color][/b] 20100618, 1,117.51, %Chg: 2.74 20100716, 1,064.88, %Chg: -4.71 20100820, 1,071.69, %Chg: 0.64 20100917, 1,125.59, %Chg: [b][color=Blue]5.03[/color][/b] 20101015, 1,176.19, %Chg: 4.50 20101119, 1,199.73, %Chg: 2.00 20101217, 1,243.91, %Chg: 3.68 20110121, 1,283.35, %Chg: 3.17 20110218, 1,343.01, %Chg: 4.65 20110318, 1,279.20, %Chg: -4.75 20110415, 1,319.68, %Chg: 3.16 20110520, 1,333.27, %Chg: 1.03 20110617, 1,271.50, %Chg: -4.63 20110715, 1,316.14, %Chg: 3.51 20110819, 1,123.53, %Chg: [b][color=Red]-14.63[/color][/b] 20110916, 1,216.01, %Chg: [b][color=Blue]8.23[/color][/b] 20111021, 1,238.25, %Chg: 1.83 20111118, 1,215.65, %Chg: -1.83 20111216, 1,219.66, %Chg: 0.33 20120120, 1,315.38, %Chg: [b][color=Blue]7.85[/color][/b] 20120217, 1,361.23, %Chg: 3.49 20120316, 1,404.17, %Chg: 3.15 20120420, 1,378.53, %Chg: -1.83 20120518, 1,295.22, %Chg: [b][color=Red]-6.04[/color][/b] 20120615, 1,342.84, %Chg: 3.68 20120720, 1,362.66, %Chg: 1.48 20120817, 1,418.16, %Chg: 4.07 20120921, 1,460.15, %Chg: 2.96 20121019, 1,433.19, %Chg: -1.85 20121116, 1,359.88, %Chg: [b][color=Red]-5.12[/color][/b] 20121221, 1,430.15, %Chg: [b][color=Blue]5.17[/color][/b] 20130118, 1,485.98, %Chg: 3.90 20130215, 1,519.79, %Chg: 2.28 20130315, 1,560.70, %Chg: 2.69 20130419, 1,555.25, %Chg: -0.35 20130517, 1,667.47, %Chg: [b][color=Blue]7.22[/color][/b] 20130621, 1,592.43, %Chg: -4.50 20130719, 1,692.09, %Chg: [b][color=Blue]6.26[/color][/b] TOTAL MONTHS = 615 DOWN MONTHS = 238 UP MONTHS = 377 %UP MONTHS = 61.3% AVG %UP MONTH = 3.2% %DOWN MONTHS = 38.7% AVG %DOWN MONTH = -3.5%