ABSTRAK Saat ini terdapat banyak Koperasi susu yang berkembang di Yogyakarta. Salah satunya adalah Koperasi susu di UPP Kaliurang yang memproduksi susu segar. UPP Kaliurang adalah koperasi yang bersifat Make to Stock yang belum didukung dengan perencanaan dan pengendalian produksi yang baik. Seringkali koperasi tidak memiliki gambaran yang tepat untuk memproduksi produknya, sehingga membuat koperasi sering tidak dapat memenuhi permintaan konsumen. Permintaan perlu dilakukan untuk memberi gambaran akan permintaan konsumen dimasa yang akan datang dan dapat dibuat perencanaan persediaan yang sesuai. Metode P merupakan salah satu pengendalian perediaan bahan baku yang dapat digunakan. Metode P ini merupakan sistem pengendalian persediaan yang membahas tentang bagaimana menerapkan kebijakan yang dapat meminimalkan biaya persedian, sehingga diharapkan dapt melakukan pengendalian persediaan produk susu segar di UPP Kaliurang. Hasil identifikasi menunjukan bahwa total biaya per bulan minimal diperoleh apabila UPP Kaliurang menerapkan kebijakan menggunakan sistem P yaitu dengan besarnya interval waktu pemesanan (T) selama 1,36 hari (32 jam 38 menit), jumlah pemesanan (R) sebesar 4000 liter dan perkiraan kekurangan produk (N) sebesar 30,9. Sehingga total biaya persediaan yang dikeluarkan oleh UPP Kaliurang adalah sebesar Rp 19.134.158,32..
Kata Kunci: Perencanaan Persediaan, Metode P, Total biaya
ABSTRACT Today, there are many milk cooperation that growing up in Yogyakarta. One of them is Milk Cooperation at UPP Kaliurang who producing fresh milk. UPP Kaliurang is cooperation that characterized Make to Stock that has not been supported with well production planning and controlling. Often the cooperation doesn’t have an adequate image for their production, as consequence the cooperation could not fulfill their consumer’s demand. Demand is necessitated to provide an image on future consumer’s demand and as reference for appropriate inventory planning. The P method is a one of control for raw material inventory that can be used. This P method is an inventory control system that focusing on implementation of policy for reducing inventory cost. Therefore it is expectable to inventory control of fresh milk at UPP Kaliurang can be performed. The identification result is presenting that the total cost of per month minimum if UPP Kaliurang implementing the policy that using P system with order time interval value (T) as long as 1,36 days (32 hours, 38 minutes), total order value (R) as much as 4000 litters and the expectation value (N) as much as 30,9. So that the total inventory cost that spent by UPP Kaliurang as much as Rp 19.134.158,32. Keyword: Inventory Planning, P method, Total Cost
DAFTAR ISI Halaman Judul..........................................................................................
i
Halaman Pengesahan................................................................................
ii
Kata Pengantar..........................................................................................
iii
Daftar Isi...................................................................................................
v
Daftar Tabel..............................................................................................
ix
Daftar Gambar..........................................................................................
x
Daftar Lampiran........................................................................................
xi
Abstrak.......................................................................................................
xii
Abstract.....................................................................................................
xiii
BAB I PENDAHULUAN 1.1
Latar Belakang.....................................................................
I-1
1.2
Perumusan Masalah................................................................ I-3
1.3
Batasan Masalah dan Asumsi................................................ I-3 1.3.1 Batasan masalah.........................................................
I-3
1.3.2Asumsi........................................................................
I-4
1.4
Tujuan Penelitian.................................................................
I-4
1.5
Manfaat Penelitian...............................................................
I-4
BAB II LANDASAN TEORI 2.1
Peramalan Permintaan....................................................
II-1
2.1.1 Karakteristik peramalan.........................................
II-1
2.1.2 Prinsip-prinsip peramalan......................................
II-2
2.1.3 Metode-metode peramalan.....................................
II-3
2.1.4 Klasifikasi peramalan............................................
II-6
2.1.5 Ukuran hasil peramalan............................................
II-9
2.1.6 Verifikasi peramalan................................................
II-11
2.2 Persediaan............................................................................
II-12
2.3 Fungsi dan Tujuan Pengendalian Persediaan......................
II-13
2.4 Biaya-biaya dalam Sistem Persediaan...............................
II-14
2.5 Jenis-jenis Sistem Persediaan............................................
II-17
2.6 Faktor-faktor yang Mempengaruhi Persediaan...................
II-19
2.7 Pengendalian Persediaan Probabilistik dengan Metode P (Periodic
BAB III
Review)................................................................................
II-22
2.7.1 Karakteristik model P................................................
II-23
2.7.2 Asumsi model P........................................................
II-25
2.7.3 Model P dengan back order.......................................
II-26
METODOLOGI PENELITIAN
3.1
Objek Penelitian...................................................................
III-1
3.2
Data-data yang Dibutuhkan.................................................
III-1
3.3
Teknik Pengumpulan Data...................................................
III-1
3.4
Kerangka Penelitian.............................................................
III-2
3.5
Metode Pengolahan Data................................................
III-4
BAB IV
PENGOLAHAN DATA DAN ANALISIS HASIL
4.1
Pengumpulan Data...............................................................
IV-1
4.2
Pengolahan Data..................................................................
IV-3
4.2.1 Peramalan............................................................
IV-3
4.2.2 Verifikasi hasil peramalan....................................
IV-4
4.2.3 Perhitungan Total Biaya Persediaan berdasarkan Periodic Review................................................................ 4.3
BAB V
Analisis Hasil................................................................
IV-7 IV-14
KESIMPULAN DAN SARAN
5.1
Kesimpulan........................................................................
V-1
5.2
Saran..................................................................................
V-1
DAFTAR PUSTAKA LAMPIRAN
DAFTAR TABEL Tabel 4.1
Permintaan Produk Susu Segar.........................................
IV-1
Tabel 4.2
Tingkat Kesalahan Peramalan..........................................
IV-4
Tabel 4.3
Hasil Perhitungan Moving Range...................................
IV-5
Tabel 4.4
Hasil Peramalan Susu Segar untuk Periode Mendatang..... IV-7
Tabel 4.5
Hasil Perhitungan Standar Deviasi....................................
IV-8
Tabel 4.6
Perhitungan Metode P........................................................
IV-9
Tabel 4.7
Hasil Perhitungan T...........................................................
IV-14
DAFTAR GAMBAR
Gambar 2.1
Pola Data Random...........................................................
II-7
Gambar 2.2
Pola Data Siklus..............................................................
II-8
Gambar 2.3
Pola Data Musiman........................................................
II-8
Gambar 2.4
Pola Data Trend........................................................ ....
II-9
Gambar 2.5
Situasi Persediaan dengan Metode P............................
II-24
Gambar 3.1
Diagram Alir Penelitian............................................ ....
III-3
Gambar 4.1
Plot Data Permintaan Susu Segar................................
IV-3
Gambar 4.2
Peta Kendali Moving Range.......................................
IV-6
DAFTAR LAMPIRAN
Lampiran 1
Hasil Peramalan dalam 3 Metode
Lampiran 2
Tabel Distribusi Normal
Lampiran 3
Tabel Distribusi Normal dalam Buku Tersine, 1994
