API Port Graph urlencode

I’m having some issues trying to access port graphs for ports with forward slashes in the path. I tried urlencoding like mentioned in the docs, but not having any luck. Any ideas?

curl -k -H 'X-Auth-Token: *hidden*' https://hostname/api/v0/devices/device_name/ports/ifName?ifName=xe-0/0/37
{
    "status": "ok",
    "port": {
        "in_rate": "0 bps",
        "out_rate": "0 bps",
        "in_perc": "nan",
        "out_perc": "nan",
        "in_pps": "0 ",
        "out_pps": "0 "
    },
    "count": 6
curl -k -H 'X-Auth-Token: *hidden*' https://hostname/api/v0/devices/device_name/ports/xe-0%2F0%2F37/port_bits
<!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML 2.0//EN">
<html><head>
<title>404 Not Found</title>
</head><body>
<h1>Not Found</h1>
<p>The requested URL /api/v0/devices/device_name/ports/xe-0/0/37/port_bits was not found on this server.</p>
</body></html>