Concentrations of credit risk and major customers (Tables)

12 Months Ended

Sep. 30, 2018

Risks and Uncertainties [Abstract]

Schedule of revenue recognized from customers

For each of the years ended September 30, 2018, our total revenue was derived from the following customers:

	Year ended September 30,
	2018		2017		2016
State and local government agencies	51	%	49	%	46	%
Foreign government agencies	27	%	26	%	26	%
U.S. Federal Government agencies	16	%	19	%	22	%
Other sources	6	%	6	%	6	%

The proportion of revenue recognized from customers providing in excess of 10% of our consolidated revenue for each of the three years ended September 30, 2018, was as follows:

	Year ended September 30,
	2018		2017		2016
U.S. Federal Government	16	%	19	%	22	%
New York	16	%	15	%	12	%
United Kingdom	12	%	12	%	16	%
Australia	10	%	*		*

______________________

* Government provided less than 10% of our consolidated revenue in this fiscal year.