Progress Calendar in SwiftUI

I'm building a progress calendar feature in my app. There is a progress bar in my app, if the user reaches 100% at the current day, I want to show them a checkmark in the calendar so they can see in which days they completed their goal. What would be the way to build it? I guess I can have a variable for each day of the month and make it true if the user reaches 100% for that day, but that seems like a really bad solution.
Here is my calendar usage.

Code Block
CalendarView(interval: year) { date in
if calendar.component(.day, from: date) == calendarCurrent.component(.day, from: currentDate) {
ZStack {
Text("30")
.hidden()
.padding(8)
.overlay(
RoundedRectangle(cornerRadius: 10,
style: .continuous)
.stroke(Color(red: 50/255, green: 104/255, blue: 144/255), style: StrokeStyle(lineWidth: 2)))
.padding(.vertical, 4)
.overlay(
Text(String(self.calendar.component(.day, from: date))).bold())
.foregroundColor(.white)
}
} else {
ZStack {
Text("30")
.hidden()
.padding(8)
.background(Color(red: 50/255, green: 104/255, blue: 144/255))
.clipShape(RoundedRectangle(cornerRadius: 10))
.padding(.vertical, 4)
.overlay(
Text(String(self.calendar.component(.day, from: date))).bold())
.foregroundColor(.white)
}
}
}