IBM Managed Security Services says number of industrial control systems (ICS) increased by 110 percent in 2016 compared to 2015. IBM: The spike is associated with a significant increase to brute force attacks on SCADA systems. Threat actors in the US accounted for the majority of ICS attacks in 2016 (60%) followed by Pakistan (20%), and China (12%) The United States also topped the list of the top 5 destination countries, this data is considered normal by experts because the US has the largest number of internet-connected ICS systems in the world.”]
Source: https://securityaffairs.co/wordpress/54792/security/ics-attacks-2016.html