RuneScape:Grand Exchange Market Watch/Adjustments (19 June 2014)

19 June 2014

Adjusted index: Discontinued Rare Index Adjustment date: 19 June 2014 Affected templates: Template:GE Discontinued Rare Index and Template:GE Discontinued Rare Index/Diff Added item(s): Cloak of Seasons Removed item(s): None Items before adjustment: 19 Items after adjustment: 20 Divisor before adjustment: 15.2787 Divisor after adjustment: 15.3476 Item Base date Base price Price on adjustment date Comments Christmas cracker 31 December 2008 688,800,000 2,147,483,644 Unchanged Blue partyhat 340,100,000 2,147,483,647 Green partyhat 114,800,000 1,512,978,741 Purple partyhat 83,100,000 1,242,748,792 Red partyhat 129,400,000 1,706,390,538 White partyhat 183,300,000 2,147,481,758 Yellow partyhat 96,300,000 1,325,097,236 Pumpkin 5,300,000 157,608,053 Easter egg 4,300,000 62,666,643 Blue h'ween mask 12,800,000 121,249,470 Green h'ween mask 10,600,000 98,258,298 Red h'ween mask 17,300,000 170,663,885 Santa hat 14,800,000 125,533,632 Disk of returning 4,700,000 211,466,440 Half full wine jug 31,100,000 348,603,157 Fish mask 29 September 2012 4,555,462 669,574 Christmas tree hat 20 January 2013 2,295,576 12,559,556 Crown of Seasons 23 July 2013 8,307,542 4,555,009 Black Santa hat 20 January 2013 222,967,707 410,924,805 Cloak of Seasons – – 7,614,236 Added item Calculations From the old divisor obtained from the templates: ${div}_{\text{old}} = 15.2787$ We need to calculate a new divisor: ${div}_{\text{new}} = {div}_{\text{old}} \times \frac{\sum \left ( \frac{p}{q} \right )_{\text{new}}}{\sum \left ( \frac{p}{q} \right )_{\text{old}}}$ To calculate the new divisor, we need to find: $\begin{align} \sum \left ( \frac{p}{q} \right )_{\text{old}} & = \text{sum of ratios prior to change} \\ & = \frac{2,147,483,644}{688,800,000} + \frac{2,147,483,647}{340,100,000} + \frac{1,512,978,741}{114,800,000} + \dots + \frac{4,555,009}{8,307,542} + \frac{410,924,805}{222,967,707} \\ & = 221.84047459 \text{ (up to 8 d.p.)} \end{align}$ And also: $\begin{align} \sum \left ( \frac{p}{q} \right )_{\text{new}} & = \text{sum of ratios prior to change} - \text{sum of removed ratios} + \text{sum of added ratios} \\ & = \sum \left ( \frac{p}{q} \right )_{\text{old}} - \text{sum of removed ratios} + \text{number of added items} \\ & = 221.84047459 - 0 + 1 \\ & = 222.84047459 \text{ (up to 8 d.p.)} \end{align}$ Thus, the new divisor is: $\begin{align} {div}_{\text{new}} & = {div}_{\text{old}} \times \frac{\sum \left ( \frac{p}{q} \right )_{\text{new}}}{\sum \left ( \frac{p}{q} \right )_{\text{old}}} \\ & = 15.2787 \times \frac{222.84047459}{221.84047459} \\ & = 15.3476 \text{ (4 d.p.)} \end{align}$