German intelligence: ISIS lost critical oil-fields, running out of money
http://www.sueddeutsche.de/politik/versorgungsengpaesse-fuer-terrormiliz-der-is-sitzt-auf-dem-trockenen-1.2425961
(article in german)
The german secret intelligence agency BND has compiled a report that says that ISIS recently lost 3 major oil-fields to kurdish and iraqi counter-attacks. This means that their oil-production is down to 5% of the former capacity.
It is important to note that ISIS demolished equipment and set the oil-fields on fire, possibly hinting that ISIS itself doesn't believe it can reclaim the oil-fields.
ISIS could conquer syrian oil-fields, but they are of small capacity and the equipment is badly maintained. And on top of that, IS is running out of engineers that can operate the equipment.
The estimates for the monetary value of IS vary from $1 billion to $3 billion.
The last weeks have seen several reports surface that mention that IS has difficulties obtaining supplies. Among others, providing electricity and water has become difficult. There are rumors that IS raised the taxes in its area and that combat-morale of ISIS is dwindling.