aggregate plugin showing stacked

gistfile1.txt

[aggregates;firewall]
  update no
  contacts no

  bandwidth.graph_title Aggregate Bandwidth
  bandwitdh.graph_category network

  bandwidth.graph_order \
    ipv6_up=example.com;firewall.example.com:if_ppp1.up \
    ipv4_up=example.com;firewall.example.com:if_ppp0.up \
    ipv6_down=example.com;firewall.example.com:if_ppp1.down \
    ipv4_down=example.com;firewall.example.com:if_ppp0.down

  bandwidth.ipv4_down.cdef 0,ipv4_down,-

  bandwidth.ipv6_down.cdef 0,ipv6_down,-

  bandwidth.ipv6_down.colour ff00ff
  bandwidth.ipv4_down.colour 0000ff
  bandwidth.ipv4_up.colour 0000ff
  bandwidth.ipv6_up.colour ff00ff

  bandwidth.ipv6_up.draw AREA
  bandwidth.ipv4_up.draw STACK

  bandwidth.ipv6_down.draw AREA
  bandwidth.ipv4_down.draw STACK