Code Golf
Given a list of positive integers, output how many items are strictly less than the previous item. The first item will never be counted.
### Test cases
|`[1 2 5 8 12 21 51]`|`0`|
|`[4 2 5 2 1 5 2]`|`4`|
|`[4 5 3 6 2 7 1 8]`|`3`|
|`[3 3 3 1 1 1]`|`1`|
Top Answer APL (Dyalog Unicode)
# [APL (Dyalog Unicode)], 6 [bytes]( "When can APL characters be counted as 1 byte each?") [^SBCS^]( ".dyalog files using a single byte character set")

Anonymous tacit prefix function. The rare case of ASCII-only APL!

[Try it online!][TIO-k84oab5w]

|`+`|the numbers
|`2>/`|pairwise greater-than

[APL (Dyalog Unicode)]:
[TIO-k84oab5w]: "APL (Dyalog Unicode) – Try It Online"
Answer #2
# [Jelly], 3 bytes


[Try it online!][TIO-khpcph9k]

[TIO-khpcph9k]: "Jelly – Try It Online"

## Explanation

    >ƝS   Main monadic link
     Ɲ    For each pair of neighboring elements:
    >       Is greater than?
      S   Sum
Answer #3 Kotlin
# Kotlin, 33 bytes


[Try it online!][TIO-khpwsdik]

[TIO-khpwsdik]: "Kotlin – Try It Online"
Answer #4
# [Runic Enchantments], 24 bytes


[Try it online!][TIO-khv468eu]

[Runic Enchantments]:
[TIO-khv468eu]: "Runic Enchantments – Try It Online"

The `l}i{l1-(  ?` section handles reading input (and if there is more input to read). There isn't, `~$;` is called, printing the answer and terminating, otherwise the `3*` results in a jump to `:4s)+S`, checking for less-ness and incrementing the counter. `2?` then insures that looping resumes at the correct position.

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