DAX measure with month variable based on date field - powerbi

Question

I am having a hard time getting the following measure to work. I am trying to change the target based on a date filter. My filter is the Workday columns, where Workday is a standard date column. sMonth is a month columns formatted as whole number. I am looking to keep the slicer granular, in order to work by day, adding custom columns with month and year and basing the measure on those would help. This is what I have tried and couldn't get it to work:
Cars Inspected =
VAR
selectedMonth = MONTH(SELECTEDVALUE('All Cars Inspected'[Workday]))
RETURN CALCULATE(SUM(Targets[Target]),
FILTER(Targets,Targets[Location]="Texas"),
FILTER(Targets,Targets[Description]="CarsInspected"),
FILTER(Targets,Targets[sMonth]=selectedMonth))
I would appreciate if someone would suggest a different way of achieving the same result.
LE:
This is a mock-up of what I am trying to achieve:
The total cars get filtered by the Workday. I would like to make the Targets/Ranges dynamic. When the slider gets adjusted everything else is adjusted.
My tables look like this:
+-----------+--------------------+----------+
| Workday | TotalCarsInspected | Location |
+-----------+--------------------+----------+
| 4/4/2017 | 1 | Texas |
| 4/11/2017 | 149 | Texas |
| 4/12/2017 | 129 | Texas |
| 4/13/2017 | 201 | Texas |
| 4/14/2017 | 4 | Texas |
| 4/15/2017 | 6 | Texas |
+-----------+--------------------+----------+
+----------+--------+----------+---------------+--------+-----+--------+
| TargetID | sMonth | Location | Description | Target | Red | Yellow |
+----------+--------+----------+---------------+--------+-----+--------+
| 495 | 1 | Texas | CarsInspected | 3636 | 0.5 | 0.75 |
| 496 | 2 | Texas | CarsInspected | 4148 | 0.5 | 0.75 |
| 497 | 3 | Texas | CarsInspected | 4861 | 0.5 | 0.75 |
| 498 | 4 | Texas | CarsInspected | 4938 | 0.5 | 0.75 |
| 499 | 5 | Texas | CarsInspected | 5094 | 0.5 | 0.75 |
| 500 | 6 | Texas | CarsInspected | 5044 | 0.5 | 0.75 |
| 501 | 7 | Texas | CarsInspected | 5043 | 0.5 | 0.75 |
| 502 | 8 | Texas | CarsInspected | 4229 | 0.5 | 0.75 |
| 503 | 9 | Texas | CarsInspected | 4311 | 0.5 | 0.75 |
| 504 | 10 | Texas | CarsInspected | 4152 | 0.5 | 0.75 |
| 505 | 11 | Texas | CarsInspected | 3592 | 0.5 | 0.75 |
| 506 | 12 | Texas | CarsInspected | 3748 | 0.5 | 0.75 |
+----------+--------+----------+---------------+--------+-----+--------+

Answer 1

Let the Value for your gauge be the sum of TotalCarsInspected and set the Maximum value to the following measure:
Cars Inspected =
VAR selectedMonth = MONTH(MAX('All Cars Inspected'[Workday]))
RETURN LOOKUPVALUE(Targets[Target],
Targets[Location], "Texas",
Targets[Description], "CarsInspected",
Targets[sMonth], selectedMonth)