Wrong historic exchange rates with EUR as base

[makemate]

I've tried to get historic exchange rates for EUR and USD. When using EUR as base currency there appeared sometimes unrealistic high values for USD. I couldn't find the bug in the code base but this is the code in python 2.7 I've been using:

import datetime
c = CurrencyRates(force_decimal=False)
d = datetime.datetime(2018, 5, 1, 18, 36, 28, 151012)
for t in range(100):
    try:
        ex_rate= c.get_rate('EUR', 'USD', (d - datetime.timedelta(days=t)))
        ex_rates = c.get_rates('EUR', (d - datetime.timedelta(days=t)))
        if ex_rate > 1.6:
            print ex_rate, ex_rates, d - datetime.timedelta(days=t)
    except Exception, e:
        print 'Exchange rate not available' 

When using USD as base rate this error didn't appear.

[ashwin31]

@makemate this is fixed and verified.