diff --git a/stdlib/Dates/src/periods.jl b/stdlib/Dates/src/periods.jl
index c88a1bed4bba9..8f28f95d4a90e 100644
--- a/stdlib/Dates/src/periods.jl
+++ b/stdlib/Dates/src/periods.jl
@@ -451,11 +451,11 @@ toms(c::Second)      = 1000 * value(c)
 toms(c::Minute)      = 60000 * value(c)
 toms(c::Hour)        = 3600000 * value(c)
 toms(c::Period)      = 86400000 * days(c)
-toms(c::CompoundPeriod) = isempty(c.periods) ? 0.0 : Float64(sum(toms, c.periods))
+toms(c::CompoundPeriod) = isempty(c.periods) ? 0.0 : sum(p -> convert(Float64, toms(p))::Float64, c.periods)
 tons(x)              = toms(x) * 1000000
 tons(x::Microsecond) = value(x) * 1000
 tons(x::Nanosecond)  = value(x)
-tons(c::CompoundPeriod) = isempty(c.periods) ? 0.0 : Float64(sum(tons, c.periods))
+tons(c::CompoundPeriod) = isempty(c.periods) ? 0.0 : sum(p -> convert(Float64, tons(p))::Float64, c.periods)
 days(c::Millisecond) = div(value(c), 86400000)
 days(c::Second)      = div(value(c), 86400)
 days(c::Minute)      = div(value(c), 1440)
@@ -465,7 +465,7 @@ days(c::Week)        = 7 * value(c)
 days(c::Year)        = 365.2425 * value(c)
 days(c::Quarter)     = 91.310625 * value(c)
 days(c::Month)       = 30.436875 * value(c)
-days(c::CompoundPeriod) = isempty(c.periods) ? 0.0 : Float64(sum(days, c.periods))
+days(c::CompoundPeriod) = isempty(c.periods) ? 0.0 : sum(p -> convert(Float64, days(p))::Float64, c.periods)
 seconds(x::Nanosecond) = value(x) / 1000000000
 seconds(x::Microsecond) = value(x) / 1000000
 seconds(x::Millisecond) = value(x) / 1000