US repo grew from €214.1 billion in September 2016 to €224.6 billion at the end of September 2017, a change of 5 percent.
Nex Group also beat its August 2017 US repo volume by 5 percent, which previously stood at €225.8 billion.
The group also experienced a 24 percent growth in its annual EU volume in September.
Volume rose from $172.5 billion to $213.7 billion from September 2016 to September 2017.
According to Nex Group, geopolitical events, such as the US presidential election and Brexit result in June last year were the most significant drivers of fixed income trading over the past 12 months.