Calculating Availability Score

The availability score is a numeric score representing the resource's availability for the entity in question, based on their current load and capacity.

Note: Only the resource allocations from staffing profiles are calculated, which does not include the allocations from requests and project tasks.

A higher score (close or equal to 100) means better availability. The availability score is the average of the availability by time period (years, quarters, months, or weeks). The availability by time period is calculated from the available resource capacity (remaining capacity) over a non-zero position forecast (available resource capacity = resource capacity – resource allocation), expressed as a percentage.

Availability Score

= [ AT(1) + AT(2) + ... + AT(n) ] / N
or

 

= { [ RC(1) / PF(1) ] * 100 + [ RC(2) / PF(2) ] * 100 + ... +
      [ RC(n) / PF (n) ] * 100 } / N

where:

AT = availability by time period = ( RC / PF ) * 100
RC = available resource capacity
PF = position forecast (0 < PF <= 1)
N = number of time periods

Note: The availability by time period cannot be greater than 100% (that is, a resource cannot be available more than 100% of the time). If this calculation is greater than 100%, the availability by time period is set to 100%.

The position forecast cannot be greater than one (that is, a resource cannot be booked for more than one FTE per time period). If the position forecast is zero, the availability by time period is not used in the calculation of the availability score.

Table 5-7. Example availability score calculations

RC

PF

N

Availability by Time Period

Availability Score

.33, .25, 1

.33, .5, 1

3

(.33 / .33) * 100 = 100%

(.25 / .5) * 100 = 50%

(1 / 1) * 100 = 100%

(100% + 50% + 100% ) / 3
= 83%

.33, .25, 1

0, .5, 1

3

N/A

(.25 / .5) * 100 = 50%

(1 / 1) * 100 = 100%

( 50% + 100% ) / 2 = 75%*

*Because the position forecast is zero in the first time period, the first time period is not included in the calculation of the availability score.

Example: Availability Score for William Klein

In the following example, William Klein is an application developer who has 75% of his time allocated in May to Project A. He is also planning to take two weeks of vacation in July.

Project B requires application developers for six months from May through October. Staffing requirements are three FTEs for May through August, tapering off to one FTE for September, and 1/2 FTE for October.

The following are William Klein's capacity, allocation, available capacity, and availability by month:

Table 5-8. William Klein’s monthly availability calculations for Project B
 

May.

Jun.

Jul.

Aug.

Sept.

Oct.

Capacity

1

1

.5

1

1

1

Allocation

.75

0

0

0

0

0

Available Capacity (RC)
(Capacity - Allocation)

.25

1

.5

1

1

1

Position Forecast (PF)
(0 < PF <= 1)

1

1

1

1

1

.5

Availability by Month (AT)
( [RC / PF ] * 100, <= 100% )

25%

100%

50%

100%

100%

100%

William Klein's availability score for Project B is:

( 25% + 100% + 50% + 100% + 100% + 100% ) / 6 = 79%

Example: Availability Score for Joseph Bank

In the following example, Joseph Bank is an application developer who has 50% of his time allocated in May and June to Project A and 100% of his time allocated in September and October to Project C. He is planning to take two weeks of vacation in August.

Project B requires application developers for six months from May through October. Staffing requirements are three FTEs for May through August, tapering off to one FTE for September, and 1/2 FTE for October. William Klein is expected to be allocated to the work in September and October.

The following are Joseph Bank's capacity, allocation, available capacity, and availability by month:

Table 5-9. Joseph Bank’s monthly availability calculations for Project B
 

May.

Jun.

Jul.

Aug.

Sept.

Oct.

Capacity

1

1

1

5

1

1

Allocation

.5

.5

0

0

1

1

Available Capacity (RC)
(Capacity - Allocation)

.5

.5

1

.5

0

0

Position Forecast (PF)
(0 < PF <= 1)

1

1

1

1

0

0

Availability by Month (AT)
( [RC / PF ] * 100, <= 100% )

50%

50%

100%

50%

N/A

N/A

Joseph Bank's availability score for Project B is:

( 50% + 50% + 100% + 50% ) / 4 = 63%

Example: Availability Score for Barbara Getty

In the following example, Barbara Getty is a Java™ developer who has no time allocated from May through October. She is not planning to take any vacation during that time.

Project B requires application developers for six months from May through October. Staffing requirements are three FTEs for May through August, tapering off to one FTE for September, and 1/2 FTE for October. William Klein is expected to be allocated to the work in September and October.

The following are Barbara Getty's capacity, allocation, available capacity, and availability by month:

Table 5-10. Barbara Getty’s monthly availability calculations for Project B
 

May.

Jun.

Jul.

Aug.

Sept.

Oct.

Capacity

1

1

1

1

1

1

Allocation

0

0

0

0

0

0

Available Capacity (RC)
(Capacity - Allocation)

1

1

1

1

1

1

Position Forecast (PF)
(0 < PF <= 1)

1

1

1

1

0

0

Availability by Month (AT)
( [RC / PF ] * 100, <= 100% )

100%

100%

100%

100%

N/A

N/A

Barbara Getty's availability score for Project B is:

( 100% + 100% + 100% + 100% ) / 4 = 100%