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<br />Table 2.--0u1lier test KN values <br />The table below contains one-sided 10 percent significance level KN values for a normal distribution (Interagency <br />Advisory Committee on Water Data, 1982, after Grubbs and Beck, 1972). <br />Sample size KN value Sample size KN value Sample size KN value Sample size KN value <br />10 2.036 45 2.727 80 2.940 115 3.064 <br />11 2.088 46 2.736 81 2.945 116 3.067 <br />12 2.134 47 2.744 82 2.949 117 3.070 <br />13 2.175 48 2.753 83 2.953 118 3.073 <br />14 2.213 49 2.760 84 2.957 119 3.075 <br />t5 2.247 50 2.768 85 2.961 120 3.078 <br />16 2.279 51 2.775 86 2.966 121 3.081 <br />17 2.309 52 2.783 87 2.970 122 3.083 <br />18 2.335 53 2.790 88 2.973 123 3.086 <br />19 2.361 54 2.798 89 2.977 124 3.089 <br />20 2.385 55 2.804 90 2.981 125 3.092 <br />21 2.408 56 2.811 91 2.984 126 3.095 <br />22 2.429 57 2.818 92 2.989 127 3.097 <br />23 2.448 58 2.824 93 2.993 128 3.100 <br />24 2.467 59 2.831 94 2.996 129 3.102 <br />25 2.486 60 2.837 95 3.000 130 3.104 <br />26 2.502 61 2.842 96 3.003 131 3.107 <br />27 2.519 62 2.849 97 3.006 132 3.109 <br />28 2.534 63 2.854 98 3.011 133 3.112 <br />29 2.549 64 2.860 99 3.014 134 3.114 <br />30 2.563 65 2.866 100 3.017 135 3.116 <br />31 2.577 66 2.871 101 3.021 136 3.119 <br />32 2.591 67 2.877 102 3.024 137 3.122 <br />33 2.604 68 2.883 103 3.027 138 3.124 <br />34 2.6t6 69 2.888 104 3.030 139 3.126 <br />35 2.628 70 2.893 105 3.033 140 3.129 <br />36 2.639 71 2.897 106 3.037 141 3.131 <br />37 2.650 72 2.903 107 3.040 142 3.133 <br />38 2.661 73 2.908 108 3.043 143 3.135 <br />39 2.671 74 2.912 109 3.046 144 3.138 <br />40 2.682 75 2.917 110 3.049 145 3.140 <br />41 2.692 76 2.922 III 3.052 146 3.142 <br />42 2.700 77 2.927 112 3.055 147 3.144 <br />43 2.710 78 2.931 113 3.058 148 3.146 <br />44 2.719 79 2.935 114 3.061 149 3.148 <br />Historic Record Adjustment <br /> <br />The recalculation of the statistics of the above-base peaks is required after the detection of outliers or <br />historic information. It takes into account any zero flows or below-gage-base peaks, low outliers, high <br />outliers, and historic peaks that have been detected, as specified in Appenclix 6 of Bulletin 17B. The logical <br />basis for the calculation is the following: <br />Historic adjustment criterion: Every annual peak that exceeded some historic threshold streamflow <br />(QH) during the historic period (H) has been recorded as either a historic peak or a systematic peak (high <br />outlier). In other words, the record is complete for peaks above QH during the time period H. The historic <br />period H includes the systematic record period plus one or more years that have no systematic record. This <br />criterion implies that the unrecorded portion of the historic period contains only peaks below the threshold <br /> <br />PEAKFQ <br /> <br />6 <br /> <br />DRAFT - 1/30/98 <br />