for product in prices.keys():
    plt.plot(years,prices[product], label=product)
    plt.ylabel('Preise')
    plt.xlabel('Jahre')

    ax = plt.subplot(111)
    box = ax.get_position()

    ax.set_position([box.x0, box.y0, box.width * 0.96, box.height])
    plt.legend(loc='center left', bbox_to_anchor=(1, 0.5))


plt.show()