सबसे पुराना ज्ञान, सबसे बड़ा जोखिम

The oldest knowledge carries the greatest risk

डिजिटल संरक्षण दर — शताब्दी अनुसार 0% 25% 50% 75% 100% 12% 18% 31% 44% 67% 82% ८वीं शती 8th century ९वीं शती 9th century १०वीं शती 10th century ११वीं शती 11th century १२वीं शती 12th century १३वीं शती 13th century