Should I be concerned about quality of earnings, based on trend analysis, of cash flow accruals:

Walmart Inc., cash flow statement computation of aggregate accruals
USD $ in millions
	Jan 31, 2018	Jan 31, 2017	Jan 31, 2016	Jan 31, 2015	Jan 31, 2014
Consolidated net income attributable to Walmart	9,862	13,643	14,694	16,363	16,022
Less: Net cash provided by operating activities	28,337	31,530	27,389	28,564	23,257
Less: Net cash used in investing activities	-9,060	-13,987	-10,675	-11,125	-12,298
Cash-flow-statement-based aggregate accruals	-9,415	-3,900	-2,020	-1,076	5,063
Ratio
Cash-flow-statement-based accruals ratio	-7.84%	-3.19%	-1.60%	-0.83%	3.88%