According to the experts the US, the UK and Netherlands are top attacked countries. US was the Top targeted country (56.7%), followed by the United Kingdom (9.6%), and the Netherlands (8.6%) China is at the first place (78,5), followed by Vietnam (4.5%), South Korea (2.9%), United States (1.7%) The largest application layer attack reached 91,209 RPS (requests per second) while the longest attack DDoS lasted 47 days.”]
Source: https://securityaffairs.co/wordpress/57228/reports/global-ddos-threat-landscape-q4-2016.html