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Total pledged 2009-2014:Our costs:
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Our Impact:$344,310,000$515,000
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Under this scenario, for everyRate of leavers:0.017↓ ↓ $1,200
Cost of maintaining membership retention rate at current level, per year:
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$1+↓
Total cost of maintaining membership retention at current levels
x
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spent by Giving What We CanRate of going silent, and not giving:0.031↓ $48,000←40Median remaining working life (years) of Giving What We Can members
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we expect that around↓Accounting for leavers and silent members:↓
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$77Membership attrition rate0.048→$122,163,428Total costs:
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will be donated to highly↓ $563,000
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effective charities↓
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After discounting:
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Discount rate for future donations:0.035→$69,360,076
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Key:↓
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Input you may want to changePercentage members pledged to give:11.03↓
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Input you're not likely to change
↓↓
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Intermediate calculation stepPercentage members actually give:12.92↓
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Output↓Accounting for how much people actually donate compared to their pledge:
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Ratio of actual donations to pledged donations1.17→$81,244,984
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↓
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This document is the basis for the 'Realistic' scenario outlined in Giving What We Can's 2015 Fundraising Prospectus. You can use it to examine the assumptions we've made, and to test out your own assumptions if you think that they would make the calculation more accurate.↓
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Donations that would not have been made otherwise:Donations that would have been made anyway:
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Counter-factual donation rate (1)0.51→$41,434,942— and →$39,810,042
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↓ ↓
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↓ ↓
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Estimate for money that would not have been donated and went to top charities: Money that would have otherwise been donated, and that we've affected the destination of
Proportion of people who say we've affected their choice of charity
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Fraction of money given to top charities0.46→$19,060,073$26,274,628 ←0.66
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Top-charity equivalent value of money that would not have been donated, and does not go to top charities:Effectiveness ratioValue of us affecting the destination of donations that would have been made otherwise (3)
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You can view the document, which includes a detailed rationale for each of these assumptions, at:Effectiveness ratio (2)0.5→$11,187,434 →$13,137,314
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↓ ↓
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https://givingwhatwecan.org/impactTotal value of donations that would not have gone to charity otherwise (3)Total money we expect to move
(in top-charity-equivalent dollars)
Estimated impact
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$30,247,508 →$43,384,822 → 77.06
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Total money expected to be moved per member
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$54,096
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(1) Proportion of donations that members say they would have donated to charity if they hadn't come into contact with Giving What We Can, averaged over members
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(2) Effectiveness ratio between either a:
• top charity vs. average developing world charity
• average developing world charity vs. average developed world charity
(we have assumed that the effectiveness ratio of either 'step' is about the same)
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(3) These numbers are expressed in 2013 top-charity-equivalent dollars