Azure subscriptions in Work 365 will have a 17.7406 markup % by default 
This is because it's a calculated mark up % for the standard 15% markup for Direct CSP partners with Microsoft. 
The reverse calculation for MSRP on Azure cost is 100 x 85%= 15, then 15 divided by 85= 17.647058%. This is how Work 365 calculates the Azure markup to apply on the subscriptions. Then when the consumption is synced from Microsoft Partner Center, the markup is automatically applied to the Azure consumption. The Work 365 invoices then calculate the Azure totals including the markup %.
If preferred this markup can be adjusted directly on the subscription. To adjust the markup % on a global level go to Work 365 > Administration > Admin Hub > Subscription Management > Default Markup %. Update the value to the preferred markup %.