This is the time in years (Y-axis) that would be necessary for the BsF to lose 90% of its value if inflation was constant, at current inflation rates. Roughly, if it costs 1 BsF to buy one US dollar in 2012, the money will have lost 90% of its value when it will cost 10 BsF to buy US dollar (Dec 2014). It will have lost 90% of its value again when it will cost 100 BsF (Sep 2016), again when it will cost 1000 BsF (Jul 2017), and again when it will cost 10,000 BsF (Oct 2017).
<p>Yearly inflation rates vary enormously over a daily basis, for instance:
</p><p>1 USD = 10,390 BsF (29 Jul 2017)
</p><p>1 USD = 10,390 BsF (30 Jul 2017)
</p><p>1 USD = 12,198 BsF (1 Aug 2017)
</p><p>1 USD = 14,760 BsF (2 Aug 2017)
</p><p>1 USD = 17,980 BsF (3 Aug 2017)
</p><p>30 Jul daily inflation rate = 100*(10390/10390 - 1) = 0%.
</p><p>30 Jul yearly inflation rate = 100*[(10390/10390)^365.24 -1] = 0% 
</p><p>Time to lose 90% of value is not a finite number.
</p><p>2 Aug 2017 daily inflation rate = 100*(14,760/12,198 - 1) = 21.0% per day
</p><p>2 Aug 2017 yearly inflation rate = 100*[(14,760/12,198)^365.24 - 1] = 1.7*10<sup>32</sup>% per year
</p><p>Time to lose 90% of value at 2 Aug inflation rate: 12.1 days.
</p><p>3 Aug 2017 daily inflation rate = 100*(17,980/14,760 - 1) = 21.8% per day
</p><p>3 Aug yearly inflation rate = 100*[(14,760/12,198)^365.24 - 1] = 2.0*10<sup>33</sup>% per year
</p><p>Time to lose 90% of value at 3 Aug inflation rate: 11.7 days.
</p><p>Therefore, to inject sanity into this graph, the daily inflation rates are averaged over 301 days. In Excel for a given day X, this is computed as:
</p><p>=LOG(10; 1 + AVERAGE(daily inflation on day X-150:daily inflation on day X+150))
</p>
Data from dolartoday.com
<a href="//commons.wikimedia.org/wiki/User:Nicolas_Perrault_III" title="User:Nicolas Perrault III">Nicolas Perrault III</a>
2018-04-05
<span class="int-own-work" lang="en">Own work</span>