Microsoft for Startups $25K milestone — what time period does the $1 per workload requirement apply to?

Microsoft's documentation for the Microsoft for Startups $25,000 Azure credit milestone states that a startup must have at least 5 Azure workloads, "each with at least $1 in spend," and maintain the required workload count for approximately 60 continuous days.

I am trying to understand exactly how the $1 spend threshold per workload is calculated.

For each of the 5 workloads, does Microsoft require:

At least $1 of spend per day for each of the 60 days?

At least $1 of spend per month/billing period during the 60-day period?

At least $1 cumulative spend on the workload, after which that workload only needs to remain active/qualifying for the remainder of the 60 days?

A rolling spend threshold over some other measurement period?

For example, if an Azure service costs $0.10 per day and accumulates more than $1 after 10 days, would that workload then count toward the 5-workload requirement for the 60-day milestone?

I am specifically asking what time interval Microsoft uses when evaluating the "$1 in spend" requirement for each workload.

Documentation referenced: https://learn.microsoft.com/en-us/startups/microsoft-for-startups/getting-started-mfs#credit-milestones-and-requirements

Please clarify the actual calculation used by the Microsoft for Startups milestone system rather than restating that each workload must have at least $1 in spend.